Polypharmacy among adult and older adult users of primary care services delivered through the Unified Health System in Minas Gerais, Brazil

ABSTRACT

Objectives

To estimate the prevalence of polypharmacy (≥5 drugs) among adults and to analyze related factors.

Methods

Cross-sectional study with 1,159 interviewees distributed across 104 cities and 253 primary healthcare services delivered through the Brazilian Unified Health System. Polypharmacy-related factors were identified using logistic regression model.

Results

949 (81.8%) interviewees were using at least one medication and were included in this analysis. The prevalence of polypharmacy among them was 13.7% (95%CI:11.7–16.0%) in the general population and 33.3%(95%CI:26.1–41.4%) in older adults(≥65 years). Polypharmacy was positively associated with age (45 to 64 years, OR=2.02; 95%CI:1.03–3.94; ≥65 years, OR=4.17; 95%CI:1.92–9.17) and the following chronic diseases: stroke (OR=4.20; 95%CI:1.53–11.55); diabetes mellitus (OR=4.03; 95%CI:2.43–6.68); heart disease (OR=3.18; 95%CI:1.92–5.29); depression (OR=2.85; 95%CI:1.80–4.53); hypertension (OR=2.13; 95%CI:1.17–3.86); and dyslipidemia (OR=1.73; 95%CI:1.07–2.80).

Conclusion

This study revealed that polypharmacy is a real concern in primary health care and affects older and middle-aged adults alike. Groups of patients that are more likely to experience polypharmacy were identified. Our findings emphasize the relevance of an appropriate approach to polypharmacy driven by aging and multimorbidity.

KEYWORDS:

• Drug utilization
• polypharmacy
• potentially inappropriate medications
• pharmacoepidemiology
• primary health care
• public health

Article highlights

• Polypharmacy is a global phenomenon with rising prevalence in several countries and reflects increased life expectancy and resultant multimorbidity. Polypharmacy is a significant factor in medication-related morbidity.

• Polypharmacy is a growing challenge in primary health care and health services and may contribute to lower adherence to drug treatment, greater exposure to potentially inappropriate medications, and potentially harmful drug–drug interactions.

• This cross-sectional study investigated polypharmacy and related factors in a representative sample of 1,159 adult users of primary health care services delivered through the Unified Health System in Brazil.

• The prevalence of polypharmacy was 13.7% in the general population and 33.3% in older adults (≥ 65 years of age). Polypharmacy was associated with age, marital status and six chronic non-communicable diseases.

• Understanding the medication use profile in primary health care allows identifying groups of people that are more likely to experience polypharmacy, and planning measures to mitigate potential polypharmacy-related problems.

Author contributions

T. A. Moreira: analysis, interpretation of data and preparation of the manuscript; J. Teodoro-Alvares: conception, design, data acquisition, analysis, data interpretation, and preparation of the manuscript; M. M. Barbosa: data analysis; R. C. R. M. Nascimento: design and acquisition of data; A. A. Guerra Júnior: design and acquisition of data; F. A. Acurcio: conception, design, analysis, interpretation of data and preparation of the manuscript. All authors reviewed and contributed to the final version of the manuscript.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants, or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was funded by the National Council for Scientific and Technological Development (CNPq # 302137/2016-5) and the Coordination for the Improvement of Higher Education Personnel (CAPES # 06446004621).