Originl ppers Ft intke in ptients newly dignosed with type 2 dibetes: 4-yer follow-up study in generl prctice Floris A vn de Lr, Eloy H vn de Lisdonk, Peter L B J Lucssen, J M H Tigchelr, Sski Meyboom, Jn Mulder, Henk J M vn den Hoogen, Guy EHMRutten nd Chris vn Weel SUMMARY Bckground: Although tretment trgets for the consumption of dietry ft in ptients with type 2 dibetes mellitus re well ccepted, little is known bout the ctul ft consumption by newly dignosed ptients or the dietry djustments tht they mke in the following yers. Aims: To mesure ft intke in ptients with type 2 dibetes in generl prctice t dignosis, shortly fter dietry consulttion, nd fter 4 yers. Design of study: A prospective cohort study. Setting: Thirty-three generl prctices in The Netherlnds. Method: One hundred nd forty-four ptients with newly dignosed type 2 dibetes were referred to dieticin, nd ft consumption (the min outcome mesure) ws ssessed with 104-item food frequency questionnire t dignosis, 8 weeks following dignosis, nd fter 4 yers. Reference vlues for ft consumption were obtined from n ge-mtched smple of popultion-bsed survey. Results: At dignosis, totl energy intke ws 10.6 MJ/dy nd cholesterol intke ws 300 mg/dy. Totl ft consumption ws 40.9% of energy intke, with sturted ftty cids 15.0%, monounsturted ftty cids 14.3%, nd polyunsturted ftty cids 9.2% of energy intke. All levels, except for polyunsturted ftty cids, were significntly unfvourble compred with those for the generl popultion. After 8 weeks, consumption of sturted ftty cids hd decresed to lower level thn in the generl popultion nd ll other levels mesured were similr to those for the generl popultion. After 4 yers there ws slight increse in the consumption of totl ft nd monounsturted ftty cids, but cholesterol nd sturted ftty cid consumption hd decresed further. Conclusions: Ptients with newly dignosed type 2 dibetes hve n unfvourble ft consumption t dignosis. They dpt to more desirble consumption shortly fter dignosis, nd this improved dietry behviour is sustined for 4 yers. Recommendtions regrding consumption of totl nd sturted ft re, in contrst to those for cholesterol, not met by ptients in generl prctice. Keywords: cohort studies; dibetes mellitus type 2; dietry fts; diet, dibetic; fmily prctice; food hbits. F A vn de Lr, MD, generl prctitioner; E H vn de Lisdonk, MD, PhD, senior lecturer in generl prctice; P L B J Lucssen, MD, PhD, generl prctitioner; J M H Tigchelr, MD, generl prctitioner; J Mulder, BE, sttisticin; H J M vn den Hoogen, sttisticin; C vn Weel, MD, PhD, professor of generl prctice; University Medicl Centre Nijmegen, Deprtment of Generl Prctice, Nijmegen. S Meyboom, RD, reserch dieticin nd nutritionist, Wgeningen University, Division of Humn Nutrition, Wgeningen. G E H M Rutten, MD, PhD, professor of generl prctice, Julius Centre for Helth Sciences nd Primry Cre, Utrecht, The Netherlnds. Address for correspondence Floris vn de Lr, UMC Nijmegen, Deprtment of Generl Prctice, 229 HAG, PO Box 9101, 6500 HB Nijmegen, The Netherlnds. E-mil: f.vndelr@hg.umcn.nl Submitted: 17 July 2003; Editor s response: 30 September 2003; finl cceptnce: 9 December 2003. British Journl of Generl Prctice, 2004, 54, 177-182. Introduction THE tretment of type 2 dibetes mellitus requires counselling on lifestyle modifictions nd dietry dvice. Consulttion with registered dieticin is dvised in most guidelines for type 2 dibetes. 1-2 The recommended dietry dvice should be tilored to ptients individul needs nd ims. Diet therpy ims to reduce risk fctors such s being overweight nd dyslipidemi. To chieve these ims, (modest) weight loss by reducing totl energy intke nd the proportion of totl ft (<30% of energy intke), s well s reduction of sturted ft intke (<10% of energy intke) nd cholesterol intke (<300 mg/dy), re strongly recommended. Moreover, minimising trns-unsturted ftty cid intke nd modest intke of polyunsturted ft (~10% of energy intke) re dvised (Box 1). 1 Although these guidelines re bsed on solid evidence from mostly experimentl studies, they do not tke into ccount the norml dietry hbits of the generl popultion. This might be prtly becuse little is known bout the ft consumed by recently dignosed ptients with type 2 dibetes in generl prctice, or bout ltertions in dietry hbits fter dignosis nd tretment. In the United Kingdom (UK) prospective dibetes study, the intke of totl ft in smple of 65 ptients, both t bseline (38.2% of energy intke) nd fter 3 yers (36.9% of energy intke), ws higher thn the recommended 30 35% of energy intke. 3 Dt from Dutch cross-sectionl study showed no significnt differences between dibetic nd non-dibetic subjects regrding totl energy intke or the consumption of totl, sturted or polyunsturted fts. 4 The need for sensible tretment trgets, which re rooted in the popultion for which they re imed, hs been discussed before in reltion to type 2 dibetes. So fr, trgets for the tretment of type 2 dibetes do not ccount for wht is fesible for ptients to chieve in norml dily life. 5 We therefore investigted the ft consumption of ptients with newly dignosed type 2 dibetes in generl prctice. The development of type 2 dibetes is ssocited with unfvourble eting hbits, such s high consumption of totl nd sturted ft. 6-8 We expected tht the mount of energy, nd the mount nd type of dietry ft consumed by ptients newly dignosed with type 2 dibetes would be unfvourble when compred with the intke of the generl popultion. Confirmtion of this hypothesis would support the bove mentioned dvice to refer ll newly dignosed ptients with type 2 dibetes to dieticin. We conducted our study with the following reserch questions: British Journl of Generl Prctice, Mrch 2004 177
F A vn de Lr, E H vn de Lisdonk, P LBJ Lucssen, et l HOW THIS FITS IN Wht do we know? Advice on ft consumption is considered to be n importnt issue for the tretment of ptients with type 2 dibetes, but the ctul ft consumption of these ptients in generl prctice is not known. Nor is it known to wht extent ptients djust their diets fter dignosis while receiving usul cre by their generl prctitioner. Wht does this pper dd? This study showed tht ptients with type 2 dibetes hve n unfvourble ft consumption. However, shortly fter dignosis nd dietry counselling, ptients ft consumption improves significntly. These improvements re mintined 4 yers fter dignosis. Wht is the ft consumption of ptients with newly dignosed type 2 dibetes in Dutch generl prctice compred with reference vlues for the generl popultion? Wht re the ltertions in ft consumption 8 weeks fter the initil dignosis nd referrl to dieticin, ccording to the Dutch guidelines for tretment of type 2 dibetes? 2 Wht is the ft consumption fter 4 yers of follow-up compred with initil consumption in these ptients? Method This study ws designed s prospective cohort study. Reference vlues for the generl popultion were obtined from the Dutch ntionl food consumption survey (DNFCS) 1998. 9 Ptients nd prctices Forty-six generl prctitioners (GPs), working in 33 generl prctices throughout The Netherlnds, included ptients with newly dignosed type 2 dibetes ged between 40 nd 70 yers in the study. Dibetes mellitus ws defined ccording to the criteri estblished by the World Helth Orgniztion: 10 ptients were eligible for the study when they hd symptoms suggestive of dibetes mellitus nd fsting blood glucose 6.7 mmol/l nd <20.0 mmol/l. In ptients with symptomtic newly dignosed dibetes, the fsting blood glucose hd to be 6.7 mmol/l on two or more occsions. Tretment In ccordnce with the Dutch guidelines for the tretment of type 2 dibetes mellitus, 2 ll included ptients were referred to registered dieticin. Dietry intervention consisted of two consulttion sessions within 4-week period, in which ptients received dietry dvice concerning ll spects of medicl nutritionl therpy for dibetes, tilored to their individul needs. The dieticins were informed bout bseline ft consumption in ll ptients. Otherwise, the dieticins did not receive extr trining or use specil protocols. Ptients Optimistion of ft consumption is n essentil prt of the dietry tretment of ptients with type 2 dibetes mellitus. In generl, the recommendtions re similr to those of the generl popultion iming t reduction of the consumption of sturted ftty cids nd cholesterol. The min sources of sturted ftty cids in The Netherlnds re met, spreds, nd diry products. The totl mount should be reduced or replced by poly- or monounsturted ftty cids. To chieve this, met from pork or beef should be replced by poultry, gme or fish, which contin lot of polyunsturted ftty cids. Olive oil is rich in monounsturted ftty cids, therefore it is recommended tht olive oil is used insted of butter for frying. Cholesterol is consumed lmost exclusively from egg yolk so egg consumption (or products tht contin egg yolk) should be minimised. Box 1. Dietry recommendtions for ptients with type 2 dibetes in The Netherlnds. who still hd fsting blood glucose 6.7 mmol/l fter 8 weeks were eligible for orl ntidibetic therpy. These ptients were sked to prticipte in 30-week rndomised controlled tril compring crbose with tolbutmide. 11 After the 30-week period, ll ptients received usul cre from their GP. Mesurements Mesurements took plce t dignosis, then fter 8 weeks, nd fter 4 yers. The consumption of dietry ft ws mesured using 104-item food frequency questionnire, in which the pst month ws used s the reference period. 12,13 This questionnire ws filled out by the ptient nd checked for errors by the investigtor. Vlues for totl energy per dy (MJ/dy), totl ft (% of energy intke), sturted ftty cids (% of energy intke), monounsturted ftty cids (% of energy intke), polyunsturted ftty cids (% of energy intke) nd cholesterol (mg/dy) were clculted using computer progrm (VET Expres 1.02, BS Nutrition Softwre, The Netherlnds) designed especilly for the questionnire. For the 4 yers mesurement, n updted version of the questionnire ws used (Wgeningen University, The Netherlnds, unpublished, 1997), including n updted clcultion progrm (Komeet 3.0, BS Nutrition Softwre, The Netherlnds). Body weight nd height were mesured without shoes nd with light clothing. Dt on medicl history, comorbidity nd use of mediction were obtined from the ptients records by their GPs. Informtion regrding ny dditionl visits to dieticin or the use of other sources for dietry informtion were recorded with the help of short questionnire. At the 4 yers follow-up, GPs mde the sme of medicl history nd comorbidity. Furthermore, GPs provided informtion bout the use of ntidibetic nd cholesterol-lowering mediction during the intervl. Centrl lbortories (Andres Hospitl, Amsterdm for bseline nd short-term, Cnisius Wilhelmin Hospitl, Nijmegen for 4 yers mesurements) used stndrd techniques nd reference rnges to mesure glycosylted hemoglobin (HbA 1c ) nd lipids. Glucose mesurements were performed loclly using clibrted glucose nlyser. 178 British Journl of Generl Prctice, Mrch 2004
Originl ppers Tble 1. Bseline chrcteristics of 144 newly dignosed ptients with type 2 dibetes in generl prctice. n Men SD Mle/femle 69/75 Age (yers) 144 57.8 8.3 Body mss index (kg/m 2 ) 134 29.5 5.2 Fsting blood glucose (mmol/l) 144 10.5 6.7 19.6 b HbA 1c (%) 131 9.0 2.6 Distolic blood pressure (mm/hg) 134 86 10 Systolic blood pressure (mm/hg) 134 145 20 Totl cholesterol (mmol/l) 130 6.2 1.1 LDL cholesterol (mmol/l) 125 3.9 1.0 HDL cholesterol (mmol/l) 126 1.1 0.3 Triglycerides (mmol/l) 131 2.7 1.5 Medin. b Rnge. HbA 1c = glycosylted hemoglobin; HDL = highdensity lipoprotein; LDL = low-density lipoprotein; SD = stndrd devition. Newly dignosed ptients with type 2 dibetes mellitus in generl prctice (1995 1998) Dignosis (n = 144) Dietry tretment 8 weeks (n = 110) Lost to 8 weeks (n = 34) Reference vlues Dt from the DNFCS 1998 were used to serve s reference vlues for ft intke by the generl popultion. The DNFCS ws cross-sectionl study of representtive smple of the Dutch popultion, comprising 6250 subjects (ged 1 97 yers) using 2-dy dietry record method. To mtch these with the cohort of ptients with newly dignosed dibetes, we used the proportion of subjects ged 40 70 yers (n = 2296). Sttisticl nlysis Results re given s men ± stndrd devition (SD). For comprison between groups (i.e., missing versus non-missing, mle versus femle), Student s two-smple t-tests were performed. For comprison of results between subsequent mesurements, Student s one-smple test ws used. Additionlly, repeted mesure nlysis ws performed to ssess n overll time effect. In order to correct for multiple testing, α ws divided by the number of tests used. Therefore, for the t-tests P<0.0024 nd for the repeted mesure nlysis P<0.0072 ws considered significnt. Ethics pprovl This study ws performed in ccordnce with the declrtion of Helsinki. The protocol for the 8-week study ws pproved by the Centrl Medicl Committee for Studies in Generl Prctice. The Locl Ethics Committee of the University Medicl Centre, Nijmegen pproved the protocol for the 4-yer study. All ptients gve their informed consent. Results The GPs included 144 ptients with newly dignosed type 2 dibetes in the study. Bseline mesurements were performed on ll 144 ptients, the 8-week mesurements were performed on 110 of the 144 ptients, nd 106 ptients prticipted in the long-term follow-up (4-yer mesurements) fter men of 3.9 yers (SD = 1.0) (Figure 1). The bseline chrcteristics of these 144 ptients re displyed in Tble 1. 4 yers (2000 2001) (n = 106) Lost to 8 weeks but recovered for 4 yers (n = 20) Lost to 4 yers (n = 24): 16 refused, 5 died, 1 not suitble ccording to GP, 2 unknown Figure 1. Study flow digrm. No 4 yers (n = 38) Lost to 4 yers (n = 14): 5 refused, 3 died, 4 moved, 1 GP refused to cooperte, 1 questionnire illegible With respect to blood glucose nd lipid profile, the study popultion ws representtive for ptients newly dignosed with type 2 dibetes. 14 The bseline results for ptients who did not prticipte in the 8-week or 4-yer evlution did not differ significntly from results of the ptients whose mesurements were not missing (dt not shown). Ft consumption Tble 2 shows the men (SD) vlues for energy intke nd ft consumption for newly dignosed ptients with type 2 dibetes t dignosis, fter 8 weeks, nd fter 4 yers. Compred with reference figures for the generl popultion, ptients hd higher intke of energy nd higher ft consumption. The men chnges for the three possible intervls re shown in Tble 3. At the 8-week follow-up, we found decrese in totl energy intke, totl ft, sturted ftty British Journl of Generl Prctice, Mrch 2004 179
F A vn de Lr, E H vn de Lisdonk, P LBJ Lucssen, et l Tble 2. Consumption of totl energy nd ft by ptients newly dignosed with type 2 dibetes compred with reference vlues for the generl popultion of similr ge. Newly dignosed ptients with type 2 dibetes Reference vlues Dignosis 8 weeks b 4 yers c for popultion d men (SD) men (SD) men (SD) men (SD) Energy intke (MJ/dy) 10.6 (3.4) 8.3 (2.2) 8.9 (2.7) 9.1 (2.8) Totl ft (En%) 40.9 (7.3) 35.5 (7.0) 37.7 (7.8) 36.3 (6.7) Sturted ftty cids (En%) 15.0 (2.8) 12.5 (2.6) 11.9 (3.1) 14.4 (3.4) Monounsturted ftty cids (En%) 14.3 (3.0) 11.8 (3.1) 12.8 (3.5) 12.6 (2.9) Polyunsturted ftty cids (En%) 9.2 (3.2) 9.3 (3.0) 9.9 (3.9) 6.8 (2.5) Cholesterol intke (mg/dy) 300.8 (123.3) 226.3 (95.2) 201.1 (99.7) 225 (112) Cholesterol intke (mg/mj) 28.7 (8.2) 27.5 (8.5) 22.5 (6.0) 25.1 (11.3) (n = 144). b (n = 110). c (n = 106). d (n = 2296). En% = % of energy intke; SD = stndrd devition. Tble 3. Chnges in consumption of totl energy nd ft by ptients newly dignosed with type 2 dibetes: men chnges from dignosis to 8 weeks, from dignosis to 4 yers, nd from 8 weeks to 4 yers. A negtive vlue indictes decrese in time. Chnge in men difference Chnge in men difference Chnge in men difference dignosis 8 weeks dignosis 4 yers b 8 weeks 4 yers c men difference (95% CI) men difference (95% CI) men difference (95% CI) Energy intke (MJ/dy) -2.2 (-2.6 to -1.7) -1.8 (-2.3 to -1.2) 0.5 d (0.09 to 0.9) Totl ft (En%) -5.1 (-6.6 to -3.5) -3.0 (-4.8 to -1.2) 2.5 (1.1 to 3.9) Sturted ftty cids (En%) -2.4 (-3.0 to -1.8) -3.1 (-3.8 to -2.3) -0.5 d (-1.1 to 0.1) Monounsturted ftty cids (En%) -2.5 (-3.1 to -1.8) -1.5 (-2.3 to -0.6) 1.0 (0.4 to 1.6) Polyunsturted ftty cids (En%) 0.3 d (-0.4 to 0.9) 0.9 d (0.0 to 1.7) 0.9 d (0.0 to 1.8) Cholesterol intke (mg/dy) -63.1 (-77.8 to -48.3) -99.7 (-120.0 to -79.4) -33.6 (-48.3 to -18.8) Cholesterol intke (mg/mj) -0.3 d (-1.5 to 1.0) -6.2 (-7.8 to -4.6) -5.6 (-7.2 to -4.0) (n = 110). b (n = 106). c (n = 86). d All vlues except these re significnt (P<0.0024).Significnce tests re done with n α of 0.0024 (0.05:21) in order to ccount for multiple testing. En% = % of energy intke. cids, nd monounsturted ftty cids. Polyunsturted ftty cids nd the reltive cholesterol intke (mg/mj) did not chnge significntly. At the 4-yer follow-up, consumption of totl ft nd monounsturted ftty cids incresed significntly compred to 8 weeks, but remined significntly lower thn the bseline. Consumption of cholesterol decresed significntly compred to bseline nd 8 weeks. Other vlues did not differ significntly from the 8 weeks mesurements. The repeted mesure nlysis showed similr results, with the exception tht the difference in consumption of totl ft between 8 weeks nd 4 yers ws not significnt. Mle nd femle ptients showed similr ft consumption t bseline, except for energy nd cholesterol intke, which ws higher in men. Women showed more profound decrese in the consumption of totl ft, monounsturted ftty cids, nd sturted ftty cids in both the 8 weeks nd 4 yers mesurements (dt not shown). When strtified for body weight (body mss index [BMI] <25, 25 nd 30, >30 kg/m 2 ), results were similr. In both our study t ll three time points, nd in the reference figures for the generl popultion, the people with BMI >30 kg/m 2 reported the lowest energy intke (dt not shown). Tble 4 reports the percentge of ptients tht met the guidelines for ft consumption. The percentge of ptients tht met the guideline regrding sturted ftty cids ( 10% of energy intke) incresed from 7.6% t bseline to 27.4% t the 4 yers mesurement. Similrly, the percentge of ptients tht consumed less thn 7% of energy intke by wy of sturted ftty cids incresed from 0.7 to 9.4%. Plsm lipids, glycemic control nd body weight After 8 weeks nd two consulttions with dieticin, 25.7% of the ptients hd fsting blood glucose <6.7 mmol/l. HbA 1c hd decresed from 9.0 to 7.8%, ll plsm lipid vlues, except for HDL-cholesterol nd triglycerids, hd improved t the 8 weeks mesurement (dt not shown). After 4 yers, HbA 1c nd plsm lipids hd significntly improved compred with the bseline nd, except for triglycerides, to the 8 weeks mesurement. BMI decresed t the 8 weeks mesurement (from 29.5 to 28.3 kg/m 2, P<0.01) but ws bck t its bseline vlue t the 4 yers mesurement. Dibetes tretment At the 4 yers mesurement, 19 of the 106 ptients (18%) were still being treted with lifestyle modifiction lone, nd for two ptients tretment for their dibetes ws unknown. The use of cholesterol-lowering medictions incresed from 10/144 (7%) t bseline, to 34/106 (32%) t the 4-yer follow-up (unknown for two ptients). On verge, fter the first two visits, ptients visited dieticin 0.6 times per yer (SD = 0.9). Seventy-seven per cent of the ptients visited dieticin less thn once yer, 13% between one nd two times yer, nd 10% hd two or more consulttions. Discussion Summry nd interprettion of min findings This study showed tht ptients in generl prctice with type 2 dibetes hd n unfvourble ft intke t the time tht the 180 British Journl of Generl Prctice, Mrch 2004
Originl ppers Tble 4. Proportion of ptients newly dignosed with type 2 dibetes t dignosis, fter 8 weeks, nd fter 4 yers, tht meet recommendtions for the consumption of ft. Newly dignosed ptients with type 2 dibetes Recommended At dignosis 8 weeks fter 4 yers fter consumption (%) dignosis b (%) dignosis c (%) of ft d Totl ft 30 En% 8.3 21.8 17.0 <30 En% 35 En% 21.5 45.5 37.7 Sturted ftty cids 7 En% e 0.7 2.7 9.4 10 En% 7.6 20.9 27.4 <10 En% 12 En% 15.3 50.0 57.5 Polyunsturted ftty cids <9 En% 41.7 39.1 40.6 9 11 En% 36.1 39.1 30.2 ~10 En% >11 En% 22.2 21.8 29.2 Monounsturted ftty cids <9 En% 2.8 11.8 13.2 9 11 En% 12.5 38.2 25.5 NSR >11 En% 84.7 50.0 61.3 Cholesterol 200 mg/dy e 16.0 47.3 54.7 300 mg/dy 60.4 84.5 93.4 <300 mg/dy (n = 144). b (n = 110). c (n = 106). d Americn Dibetes Assocition, 2002. 1e Ptients with LDL 2.6 mmol/l my benefit from sturted ftty cids 7% of energy intke nd cholesterol 200 mg/dy. En% = % of energy intke; NSR = No specific recommendtion. dibetes ws dignosed compred with reference vlues for the generl popultion. Shortly fter the first dietry consulttion, ft consumption decresed to levels similr to the generl popultion. After 4 yers, consumption of totl ft hd incresed gin, but ws still lower thn the bseline vlue. This increse ws owing to higher intke of both poly- nd monounsturted ftty cids. The intke of cholesterol hd decresed t the 8 weeks nd decresed further fter 4 yers. The observed chnges in the reported ft consumption my hve been owing to severl fctors. First, ongoing tretment for type 2 dibetes, including eduction by GPs nd dieticins, my hve hd sustined effect on ptients hbits. The ptients included in our study received usul cre by their GPs, including initil dietry dvice in two consulttions, ccording to the Dutch guidelines on dibetes. Some ptients received more consulttions through their own inititive or on dvice from their GP. No further interventions or efforts were mde to improve complince with diet. Of course, from the dt of this observtionl study we cnnot mesure the contribution of specific spects of dibetes counselling on the outcomes. But, becuse we observed ptients who received usul cre, we feel tht the presented results should be regrded s the minimlly chievble gols tht cn be reched regrding ft consumption. Second, food hbits in the generl popultion re not constnt. In the dult generl popultion of The Netherlnds, consumption of totl ft hd decresed by lmost 1% of energy intke, but sturted ftty cids hd incresed by bout 1% of energy intke from 1992 to 1998. 9 In our study, the decrese in totl ft consumption ws more profound nd the consumption of sturted ftty cids decresed. Therefore, it is not likely tht our min results re merely reflection of the trend in the generl popultion. Third, the content of foodstuffs is not constnt. Since light nd low-ft products re currently fshionble, mnufcturers my tend to chnge the mount nd type of ft in their products. In theory, it is possible tht someone who does not lter their consumption in terms of foodstuffs will hve different consumption in terms of nutrients becuse the content of the foodstuffs hs been chnged. We hve not identified studies in the literture to ssess the influence of this potentil bis. Finlly, the method of mesuring food hbits is possible source of bis. 15 All vilble instruments to mesure food intke re subject to recll bis nd, therefore, rel gold stndrd does not exist. We used semi-quntittive food frequency questionnire, wheres the reference figures for the generl popultion were bsed on dietry record method. The comprison of the dt from ptients with type 2 dibetes with those from the generl popultion should, therefore, be interpreted with cution. Strengths nd limittions of this study The min strengths of our study were tht it provided followup dt () of sufficient length, (b) in cohort of newly dignosed ptients with type 2 dibetes (dt tht provides knowledge of wht hppens during ptients creer is importnt becuse it is helpful for formulting fesible tretment gols), (c) with good long-term prticiption rte (74%), nd (d) tht were rooted in generl prctice. In The Netherlnds, s in the UK, pproximtely 75% of ptients with type 2 dibetes re treted by their GP. One of the drwbcks of our study ws tht reltively high number of ptients did not complete the food frequency questionnire t the 8 weeks mesurement: this ws prtly owing to loss of motivtion in the ptients nd the GPs. For the 4-yer follow-up, 20 of these 34 ptients could be British Journl of Generl Prctice, Mrch 2004 181
F A vn de Lr, E H vn de Lisdonk, P LBJ Lucssen, et l included gin. The possibility of selective drop out ws exmined by compring essentil chrcteristics of ptients with missing dt t short-term nd 4-yer follow-up. No significnt differences were observed, thus ttrition bis ws less probble. Furthermore, this study lcked control group. We emphsise tht this study ws not ment s n intervention study but s long-term study to ssess the chnges under usul cre. The referrl to dieticin is in concordnce with the Dutch guidelines. After the first 8 weeks from dignosis, ptients were not given extr cre regrding their lifestyle. Thus, using dibetic ptients s control group would hve been unethicl becuse, in our view, we would hve delibertely undertreted them. Agemtched helthy volunteers s controls would hve been helpful to estimte the seculr trend for ft consumption. Comprison with existing literture To our knowledge, only one previous study hs ssessed ft consumption in newly dignosed ptients with type 2 dibetes t dignosis nd fter severl yers. 3 In smll smple of the UK prospective dibetes study popultion (n = 65) hlf of the ptients complied with recommendtions regrding totl energy intke fter 3 yers of follow-up. The results of this study cnnot esily be compred with the findings in the present study becuse the types of ft were not specified. The overll decrese in totl ft consumption ws lrger in our study thn the UK prospective dibetes study (²3 versus 1% of energy intke, respectively). The differences between men nd women tht were found in the UK popultion could not be confirmed in our study. Implictions for future reserch nd policy The results regrding the percentge of ptients tht met with recommendtions might be of prticulr interest in the development of future guidelines nd tretment trgets. The most importnt tretment trgets were those for sturted ftty cids nd cholesterol consumption (<10% of energy intke nd <300 mg/dy, respectively, nd for ptients with LDL cholesterol 2.6 mmol/l, which ws the cse for most ptients in this study t dignosis, <7% of energy intke nd <200 mg/dy, respectively). Only 27% of ptients consumed less thn 10% of sturted ftty cids mesured s % of energy intke, nd only 9% of the ptients consumed less thn 7% of their energy intke by wy of sturted ftty cids. In contrst to this disppointing result, 93% (<300 mg/dy) nd 55% (<200 mg/dy) of ptients met the trget for cholesterol intke. Therefore, the trget for the consumption of cholesterol seems to be relistic nd ttinble for this generl prctice popultion, wheres the trget for the consumption of sturted ftty cids is not. This study reports ptients food hbits in terms of nutrients. We relise tht in norml dily life, ptients nd doctors do not tlk bout mono- or polyunsturted ftty cids but bout the food itself (for exmple, french fries, eggs, nd tomtoes) insted. Future reserch should investigte wht ltertions in the choice of foods re more likely to be sustined. Furthermore, better understnding of the chrcteristics of ptients who hve very good or very bd complince with dietry dvice might contribute to more effective dietry intervention strtegies. This study could help to remove some of the scepticism tht doctors hve bout the fesibility of inititing nd mintining more fvourble dietry hbits in ptients with type 2 dibetes. However, the very strict tretment trgets for the consumption of sturted ftty cids nd totl ft re not very relistic. To optimise the dietry tretment of type 2 dibetes, further lsting cre for diet nd lifestyle re importnt, but lso reconsidertion of tretment trgets for dietry fts in dibetic ptients remins necessry. References 1. 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We thnk Crl Wlk for her help with the dt collection, Kthleen Jenks nd Inge Keus for their help with the dt nlysis, nd Jenne de Vries, PhD, for her comments on the revised mnuscript. 182 British Journl of Generl Prctice, Mrch 2004