TABLE 1.
Studies Examining the Relationship Between Adherence and Health Care Use in Pediatric Populations
| Author (Year) | Study Design | Sample Size and Study Population | Measure of Adherence | Controlled For | Relationship Between Adherence and Health Care Use | |||
|---|---|---|---|---|---|---|---|---|
| ED Visits | Outpatient Visits | Hospitalizations | Other Measures of Health Care Use | |||||
| Adams et al (2001)34 | Cohort | 11 195 children (ages 3–15 yr) with asthmaa | Number of canisters or containers of drug dispenseda | Age, gender, site, reliever medication dispensing | Any dispensing of an anti-inflammatory medication was associated with a decreased risk for ED visits. Adjusted RR = 0.4 (95% CI: 0.3–0.5), P < .01 | X | Any dispensing of an anti-inflammatory medication was associated with a decreased risk for hospitalization. Adjusted RR = 0.4 (95% CI: 0.3–0.6), P < .01 | |
| Ashkenazi et al (1993)38 | Cross-sectional | 100 children (ages 2–14 y) with asthma referred to a pediatric ED; 50 children with asthma attending an HAC | Self-report measure including 2 dichotomous items assessing whether medications were taken in the dose and frequency prescribed | Compliance to prescribed dose (P < .001) and frequency (P < .001) was higher in participants in the HAC group than in the ED group | X | X | ||
| STLa | STL were higher in participants in the HAC group than in the ED group, P < .001 | X | X | |||||
| Bartlett et al (2004)40 | Cohort | 158 children with asthma | “How often does your child forget to take his/her asthma medication?” | Child age, family income, asthma morbidity, maternal depressive symptoms | NS, values not reported | X | X | |
| “In the past 2 weeks, how many days would you guess that your child has forgotten to take his or her medicine?” | Child age, family income, asthma morbidity, maternal depressive symptoms | NS, values not reported | ||||||
| Bauman et al (2002)41 | Cohort | 1199 children (ages 4–9 y) with asthmaa | Admitted non-adherence: number of times that caregivers admitted noncompliance with a physician recommendation for asthma management | X | X | Adherence was not associated with whether the child was hospitalized in the past 9 months, P = .059 | Increased adherence was associated with fewer unscheduled asthma visits (provider and ED visits), P < .001 | |
| Boylston Herndon et al (2012)36 | Cohort | 18 456 children (ages 2–18 y) with asthmaa | MPR for ICS: the percentage of days within a 365-d period that an ICS was supplied; Grouped into: 0% to 19% MPR; 20% to 49% MPR, and ≥50% MPRa | Demographics, health characteristics | ≥50% MPR was associated with lower odds of an ED visit than 0% to 19% MPR, OR = 0.56 (95% CI: 0.43–0.73), P < .001 | Greater medication adherence was associated with more frequent asthma-related office visits, P < .01 | 20% to 49% MPR was associated with increased odds of a hospital admission than 0% to 19% MPR, OR = 1.27 (95% CI: 1.04–1.55), P < .01 | Higher adherence was associated with higher per-member per-month payments |
| MPR for LI: the percentage of days within a 365-d period that an LI was supplied; Grouped into: 0% to 19% MPR; 20% to 49% MPR, and ≥50% MPRa | Demographics, health characteristics | ≥50% MPR was associated with lower odds of an ED visit than 0% to 19% MPR, OR = 0.68 (95% CI: 0.53–0.86), P = .002 | Greater medication adherence was associated with more frequent asthma-related office visits, P < .01 | NS, P = .52 | Higher adherence was associated with higher per-member per-month payments | |||
| McNally et al (2009)43 | Randomized controlled trial | 63 children (ages 5–17 y) with persistent moderate or severe asthma | Percent of prescribed oral montelukast doses received each day as recorded by an electronic monitoring device; Grouped into: low and high adherence groups based on the upper and lower quartiles of adherencea | Demographic and clinical covariates examined but not included in model owing to NS | X | X | X | Low adherence group demonstrated an increase in health care use (number of ED visits, hospitalizations, and clinic visits attributable to asthma) over the course of the study, P < .05; High adherence group demonstrated no significant change in health care use, P < .05 |
| Percent of prescribed inhaled fluticasone doses received each day as recorded by an electronic monitoring device; Grouped into: low and high adherence groups based on the upper and lower quartiles of adherencea | Demographic and clinical covariates examined but not included in model owing to NS | X | X | X | Low adherence group demonstrated an increase in health care use (number of ED visits, hospitalizations, and clinic visits attributable to asthma) over the course of the study, P < .05; High adherence group demonstrated no significant change in health care use, P < .05 | |||
| Morris et al (1997)42 | Cohort | 89 adolescents and young adults (age <30 y) with type 1 diabetesa | Number of days (out of 365) with maximum possible insulin coverage (as determined by comparing the medically recommended insulin dose with the cumulative volume of insulin prescriptions supplied); Grouped into quartilesa | X | X | Increased adherence was associated with decreased odds of admission for diabetic ketoacidosis (P < .001) Increased adherence was associated with decreased odds of hospital admissions related to complications of diabetes (P = .008) | ||
| Smith et al (2007)35 | Cohort | 1474 children (ages 2–17 y) with persistent asthmaa | Number of filled prescriptions for an inhaled corticosteroida | 1–2 filled prescriptions compared with 0 filled prescriptions decreased odds of an ED visit for asthma, Adj OR = 0.08 (95% CI: 0.05–0.15), P < .001 | X | X | ||
| Number of filled prescriptions for bronchodilatorsa | Age, gender, PCP visits, asthma PCP visits | NS in multivariate model | X | X | ||||
| Dichotomous indicator of whether a prescription for any controller medication was filled within the past 3 moa | Those with a filled prescription were less likely to have an ED visit for asthma (P < .001) than those without a filled prescription | Those with a filled prescription were more likely to have an asthma PCP visit (P < .001) than those without a filled prescription | X | |||||
| Walders et al (2004)37 | Cross-sectional | 75 children (ages 8–16 y) with persistent asthma | Total doses taken per day divided by prescribed doses per daya | Increased adherence was associated with decreased ED visits (r = −0.25, P < .05) | X | X | ||
| Zhao et al (2012)39 | Cross-sectional | 2960 children (age ≤14 y) with asthmaa | Self-reported months (out of 12) patient adhered to prescribed corticosteroid use | Increased adherence was associated with fewer ED visits, P = .00 | X | Increased adherence was associated with fewer hospitalizations, P = .00 | ||
| Self-reported months (out of 12) patient adhered to prescribed leukotriene receptor modulator use | NS, P > .05 | X | NS, P > .05 | |||||
CI, confidence interval; HAC, hospital asthma clinic; ICS, inhaled corticosteroids; LI, leukotriene inhibitors; NS, not significant; OR, odds ratio, PCP, primary care physician; STL, serum theophylline levels.
a
Representativeness of exposed cohort or assessment of outcome judged to be of high quality per Newcastle-Ottawa Quality Assessment Scale.