Table 2. Factors associated with nonadherence (N = 38).
| Factors | No of studies | Significant association with measures of nonadherence a | References | ||
|---|---|---|---|---|---|
| SPL | PSR | PC/ MEMS | |||
| Socio-demographic variables | |||||
| Age | 27 | ||||
| Younger | 8 | 8 | [23,27,41,44,45,47,48,53,54,57,61–63,65] | ||
| Older | 1 | 2 | 1 | [14,31,32,50] | |
| Gender | 22 | ||||
| Male | 1 | [61] | |||
| Female | 2 | [23,53] | |||
| Low education (high school) | 15 | 1 | [62] | ||
| Ethnicity (non-Caucasian) | 7 | 1 | 1 | 2 | [14,37,38,48] |
| Marital status (single, divorced or widowed) | 6 | 2 | [50,62] | ||
| Employment status (unemployed) | 6 | 1 | [50] | ||
| Support from health care provider | 2 | 2 | [23,45] | ||
| Family problems (illness interfering with family life) | 2 | 1 | [45] | ||
| Smoker | 1 | 1 | [14] | ||
| Clinical variables | |||||
| Long-term on HD | 16 | 3 | [23,50,63] | ||
| Comorbidity (DM, HTN) | 9 | 1 | 1 | [54] | |
| Number of hospitalization | 2 | 1 | [23] | ||
| Psycho-social variables | |||||
| Depressive symptoms | 6 | 4 | [28,31,50,61] | ||
| Belief about medicine | 5 | ||||
| Concern | 1 | 2 | [48,53,60] | ||
| Benefit | 1 | 1 | [45] | ||
| Necessity | 1 | 3 | [47,48,53] | ||
| Necessity-concern differential score | 2 | [47,53] | |||
| Health locus of control b | 3 | 2 | 1 | [46,64] | |
| Internal | 1 | [50] | |||
| Doctors | 1 | [50] | |||
| Emotional representation | 1 | 1 | [55] | ||
| Medication related factors | |||||
| Knowledge about medicine | 5 | 1 | 1 | [45,63] | |
| Number of prescribed medicines | 3 | 1 | [37] | ||
| Daily tablet count | 2 | 1 | 1 | [23,54] | |
| Total no of PB prescribed | 2 | 1 | 1 | [54] | |
| Total pill burden | 2 | 1 | 1 | [23,32] | |
| Pill burden from PB | 1 | 1 | [32] | ||
| PB equivalent dosage | 1 | 1 | [47] | ||
| Regimen complexity (frequency and dosage schedule) | 1 | 1 | [45] | ||
| Drug coverage by insurance | 1 | 1 | [26] | ||
| Health care cost (inpatient) | 1 | 1 | [29] | ||
Abbreviations: DM, diabetes mellitus; HD, haemodialysis; HTN, hypertension; MEMS, medication event monitoring system; PB, phosphate binders; PC, pill count; PSR, patient self-report; SPL, pre-dialysis serum phosphate level.
aLevel of significance (p < 0.05, p < 0.01, and p < 0.001) varies between studies.
bDefined as having high expectation that one’s actions will have a causal relationship with the consequences produced.