Impact of school-entry requirements on adolescent vaccination coverage, timeliness, & seasonal variation

Transcription

1 Impact of school-entry requirements on adolescent vaccination coverage, timeliness, & seasonal variation Jennifer L. Moss 1,2, Paul L. Reiter 3, Young K. Truong 1, Barbara K. Rimer 1, Noel T. Brewer 1 1 University of North Carolina, 2 National Cancer Institute, 3 The Ohio State University May 19, 2016

2 Disclosures JLM, YKT, and BKR have no potential conflicts to report. PLR has received a research grant from Cervical Cancer-Free America, via an unrestricted educational grant from GlaxoSmithKline. NTB has served on paid advisory boards or received research grants from Merck, GSK, and FDA, and now serves as chair of the CDCfunded National HPV Vaccination Roundtable. This research was supported by a grant from National Cancer Institute (F31 CA189411; PI: Moss) and data support from the National Center for Health Statistics. The opinions expressed are the author s own and do not reflect the view of the National Institutes of Health, the Department of Health and Human Services, or the United States government. 2

3 Human papillomavirus (HPV) and vaccine Most common sexually transmitted infection in the US High disease burden Genital warts Anogenital cancers Three, 3-dose HPV vaccines available Recommended for routine use in all year old adolescents Suboptimal rates of uptake Girls: 60% (initiation, 2014) Boys: 42% (initiation, 2014) Source: CDC, 2016; Chesson,

4 % adolescents vaccinated Adolescent vaccination coverage Revised APD* definition 1 Tdap 1 MenACWY HPV (F) 1 HPV (M) Year Source: CDC,

5 State variation in adolescent vaccination coverage (2014) Tdap MenACWY HPV 1 (girls) HPV 1 (boys) Mean 88% 79% 60% 42% Lowest 71% (ID) Highest 95% (CT) 46% (MS) 95% (PA) 38% (KS) 76% (RI) 23% (IN) 69% (RI) 1.3x 2.1x 2.0x 3.0x 5

6 School-entry requirements for vaccination Source: Immunize.org 6

7 School-entry requirements for vaccination Source: Immunize.org 7

8 School-entry requirements for vaccination Source: Immunize.org 8

9 Methods Separately for Tdap booster, MenACWY, and HPV vaccine (1 st dose, girls), examined yearly ( ) Independent variables: State policies requiring each vaccine Dependent variables: 1. Vaccination coverage (% of year olds vaccinated) 2. Timeliness (% vaccinated by age 13) 3. Summer peaks (% doses administered in June-August) Analysis: ecological, longitudinal, weighted multivariable regression 9

10 Results: States policies and vaccination patterns School-entry requirements (n), Vaccination coverage (%), Timeliness (%), Summer peaks (%), Range of values over study period Tdap booster MenACWY HPV vaccine % 42-74% 37-54% 9-67% 10-57% 11-41% 43-61% 44-62% 39-63% 10

11 % adolescents vaccinated Results: School-entry requirements and coverage 100% 90% +22% * +24% * +<1% * 80% 70% 60% 50% Without policy With policy 40% 30% 20% 10% 0% Tdap booster MenACWY HPV vaccine *p<.05 11

12 % adolescents vaccinated by age 13 Results: School-entry requirements and timeliness 100% 90% +25% * +27% * +4% * 80% 70% 60% 50% Without policy With policy 40% 30% 20% 10% 0% Tdap booster MenACWY HPV vaccine *p<.05 12

13 % doses administered June-Aug Results: School-entry requirements and summer peaks 100% 90% +5% * +6% * +25% * 80% 70% 60% 50% Without policy With policy 40% 30% 20% 10% 0% Tdap booster MenACWY HPV vaccine *p<.05 13

14 Results: Spillover effects of school-entry requirements HPV vaccination coverage by states policies about other adolescent vaccines Tdap booster policies Without With MenACWY policies Without With 44% (95% CI=41-47%) 52% (95% CI=49-54%) 47% (95% CI=44-49%) 51% (95% CI=49-53%) +8%* +4%* Remember, HPV vaccine policies associated with <1% increase in HPV vaccination coverage. *p<.05 14

15 Concomitantly vaccinated Results: School-entry requirements and concomitant vax 50% 40% Tdap + HPV +4% * MenACWY + HPV +4% * 30% 20% Without policy With policy 10% 0% Tdap booster policy MenACWY policy *p<.05 15

16 Discussion School-entry requirements associated with increases in coverage for targeted vaccines Differences in timeliness and summer peaks supports causal inference Lack of randomization Tdap booster and MenACWY requirements had spillover associations with HPV vaccination coverage Larger effect sizes than HPV vaccine requirements Potentially through concomitant vaccination 16

17 Implications 17

18 Jennifer L. Moss, PhD Cancer Prevention Fellow National Cancer 18

19 cpfp.cancer.gov

20 Methods: Independent variables States school-entry requirements (2007 to 2012) for uptake of Tdap booster MenACWY HPV vaccine Source: Immunize.org and state health department websites 20

21 Methods: Analysis Longitudinal, weighted multivariable regressions Schoolentry req. Schoolentry req. Schoolentry req. Schoolentry req. Schoolentry req. Schoolentry req. Other reqs. Other reqs. Other reqs. Other reqs. Other reqs. Other reqs. Coverage Coverage Coverage Coverage Coverage Timeliness Timeliness Timeliness Timeliness Timeliness Summer peaks Summer peaks Summer peaks Summer peaks Summer peaks 21

22 State variation in HPV vaccination coverage Kansas: 38% Rhode Island: 76% Tennessee: 20% DC: 57% 22