Under-prescription of medications in older adults according to START criteria: A cross-sectional study in Lebanon.

Background and Aims: Under-prescription is defined as the exclusion of medications indicated for the treatment of certain conditions without any rationale for not prescribing them. The under-prescription of medications is highly prevalent among older adults (≥65 years) receiving polypharmacy. This study aimed to assess the prevalence of the under-prescription of medications using the Screening Tool to Alert to Right Treatment (START) criteria version 2 and to identify the predictors of having potential prescribing omissions (PPOs).

Methods: This cross-sectional, face-to-face interview study was carried out between September 2021 and February 2022. The study comprised community-dwelling older adults taking at least one medication on a regular basis. The study questionnaire included the patients' demographics, clinical data, and comorbidities. PPOs were identified using the START criteria. The χ 2 test was used to assess the association between under-prescription of medication and the demographic/clinical variables. Multivariable logistic regression was performed to explore factors associated with under-prescription of medications as the dependent variable and taking all variables that showed a p  < 0.05 in the bivariate analysis as independent.

Results: A total of 444 older adults agreed to participate in this study. The mean age of participants was 71 ± 8.6; the majority of them, 305 (68.7%), were men. Polypharmacy was present in 261 patients (58.8%) and underprescribing of medications in 260 patients (58.6%). The highest percentage of under-prescribing of medications was reported with statins in 115 patients (44.2%) followed by aspirin in 93 (35.7%), and angiotensin-converting enzyme inhibitors in 61 (23.4%). The results of the multivariable analysis showed that patients with underprescribed medications had higher odds of polypharmacy (odds ratio [OR]: 2.015, confidence interval [CI] 95% 1.362-2.980, p  < 0.001) and higher Charlson Comorbidity Index (OR 2.807, CI 95% 1.463-5.85, p  = 0.02).

Conclusion: The present findings highlight that PPOs are highly prevalent among community-dwelling older adults in Lebanon. Multimorbidity and polypharmacy were the identified predictors for under-prescription of medications in this population.