ABSTRACT
OBJECTIVE: To evaluate age-specific multimorbidity patterns and morbidity burden on mortality and healthcare expenditure across age groups. PATIENTS AND METHODS: Retrospective observational study between January 1, 2009 to December 31, 2017 using electronic health records in Hong Kong: Individuals were stratified by age (< 50, 50-64, 65-79, ≥ 80), and sub-classified by number of morbidities (0, 1, 2, 3, ≥ 4) out of 21 common chronic conditions. Clustering analyses were conducted to identify specific patterns of multimorbidity. Association between the number as well as combinations of morbidities and all-cause mortality and public expenditure was examined. RESULTS: 4,562,832 individuals with a median follow-up of 7 years were included. Mental disorders were the top morbidities among young individuals, while cardiovascular diseases were prevalent in the elderly. An increased number of morbidities was associated with a greater relative risk for mortality and medical expenditure, and this relationship was stronger among younger patients. Compared to individuals in the same age group without morbidity, the hazard ratios (HR; 95% CI) of all-cause mortality in patients aged < 50 and ≥ 80 with two comorbidities 3.81 (3.60-4.03) and 1.38 (1.36-1.40), respectively, which increased to 14.22 (9.87-20.47) and 2.20 (2.13-2.26), respectively, as the number of morbidities increased to ≥ 4. The stroke-hypertension cluster was shown to be associated with the highest HR of mortality 2.48 (2.43-2.53) among all identified clusters arising from the clustering analysis. CONCLUSION: Given the stronger association between multimorbidity and all-cause mortality and greater opportunity costs in younger populations, prevention and management of early-onset multimorbidity are warranted. (248 words).
ABSTRACT
AIM: To evaluate the association between the number of co-morbidities, all-cause mortality and public health system expenditure in patients with type 2 diabetes (T2D) across different age groups. MATERIALS AND METHODS: A retrospective observational study of T2D patients using electronic health records in Hong Kong was conducted. Patients were stratified by age (< 50, 50-64, 65-79, ≥ 80 years) and the number of co-morbidities (0, 1, 2, 3, ≥ 4), defined using the Charlson Comorbidity Index and prevalent chronic diseases identified in local surveys. The association between the number of co-morbidities, all-cause mortality and direct medical costs was examined using Cox proportional hazard regression and the gamma generalized linear model with log link function. RESULTS: A total of 262 212 T2D patients with a median follow-up of 10 years were included. Hypertension and dyslipidaemia were the most common co-morbidities in all age groups. After age stratification, cardiovascular diseases dominated the top pair of co-morbidities in the older age groups (65-79 and ≥ 80 years), while inflammatory and liver disease were predominant among younger individuals. Compared with co-morbidity-free T2D patients, the hazard ratios (95% CI) of death for patients aged younger than 50 and 80 years or older with two co-morbidities were 1.31 (1.08-1.59) and 1.25 (1.15-1.36), respectively, and increased to 3.08 (2.25-4.21) and 1.98 (1.82-2.16), respectively, as the number of co-morbidities increased to four or more. Similar trends were observed for medical costs. CONCLUSIONS: Age-specific co-morbidity patterns were observed for patients with T2D. A greater number of co-morbidities was associated with increased mortality and healthcare costs, with stronger relationships observed among younger patients.
