Age Related Patterns of Disease and Mortality in Hospitalised Adults in Malawi

Abstract

Background: The epidemic of non-communicable diseases (NCDs) in low and middle income countries (LMICs) is widely recognised as the next major challenge to global health. However, in many LMICs, infectious diseases are still prevalent resulting in a "double burden" of disease. With increased life expectancy and longevity with HIV, older adults may particularly be at risk of this double burden. Here we describe the relative contributions of infections and NCDs to hospital admissions and mortality, according to age, in Malawi's largest hospital.

Methods: Primary diagnosis on discharge/death, mortality rates, and HIV status were recorded prospectively on consecutive adult medical in-patients over 2 years using an electronic medical records system. Diagnoses were classified as infections or NCDs and analysed according to age and gender.

Findings: 10,191 records were analysed. Overall, infectious diseases, particularly those associated with HIV, were the leading cause of admission. However, in adults ≥55 years, NCDs were the commonest diagnoses. In adults <55 years 71% of deaths were due to infections whereas in adults ≥55 years 56% of deaths were due to NCDs.

Interpretation: Infectious diseases are still the leading cause of adult admission to a central hospital in Malawi but in adults aged ≥55 years NCDs are the most frequent diagnoses. HIV was an underlying factor in the majority of adults with infections and was also present in 53% of those with NCDs. These findings highlight the need for further health sector shifts to address the double burden of infectious and NCDs, particularly in the ageing population.

Fig 1. Annual incidence of inpatient admissions per 1000 population, by age and sex, Blantyre District, Malawi 2013–2015.

The grey line represents ‘Male’, the light blue line represents ‘Female’.

Fig 2. Distribution of diagnoses of adult patients by age category, Blantyre, Malawi, 2013–2014.

The light grey hatched bars represent adults aged < 55 years; the solid dark grey bars represent adults aged 55 years and older.

Fig 3. Predicted probablility (with 95% confidence limits) of a non-communicable disease diagnosis, by age, in adult inpatients, Blantyre, Malawi- 2013 to 2014.

Fig 4. Predicted probablility (with 95% confidence limits) of a death, by age, in adult inpatients, Blantyre, Malawi- 2013 to 2014.

Fig 5. HIV Prevalence by age and sex in medical ward in-patients, Blantyre, Malawi, January 2013- December 2014.

The red line represents the percent of admitted patients that are HIV infected. The blue bars represent the number of patients admitted.