Social support and long-term mortality in the elderly: role of comorbidity.
Several studies have demonstrated a global increase in morbidity and mortality in elderly subjects with low social support or high comorbidity. However, the relationship between social support and comorbidity on long-term mortality in elderly people is not yet known. Thus, the present study was performed to evaluate the relationship between social support and comorbidity on 12-year mortality of elderly people. A random sample of 1288 subjects aged 65-95 years interviewed in 1992 was studied. Comorbidity by Charlson Comorbidity Index (CCI) score and Social Support by a scale in which total score ranges from 0 to 17, assigning to lowest social support the highest score, were evaluated. At 12-year follow-up, mortality progressively increase with low social support and comorbidity increasing (from 41.5% to 66.7% and from 41.2% to 68.3%, respectively; p<0.001). Moreover, low social support progressively increases with comorbidity increasing (and 12.4±2.5 to 14.3±2.6; p<0.001). Accordingly, multivariate analysis shows an increased mortality risk of 23% for each increase of tertile of social support scale (Hazard ratio=HR=1.23; 95% CI=1.01-1.51; p=0.045). Moreover, when the analysis was performed considering different degrees of comorbidity we found that social support level was predictive of mortality only in subjects with the highest comorbidity (HR=1.39; 95% CI=1.082-1.78; p=0.01). Thus, low social support is predictive of long-term mortality in the elderly. Moreover, the effect of social support on mortality increases in subjects with the highest comorbidity.
Mazzella
Francesca
F
Dipartimento di Medicina Clinica, Scienze Cardiovascolari ed Immunologiche, Cattedra di Geriatria, Università degli Studi di Napoli Federico II, Via S. Pansini, 5, 80131 Napoli, Italy.
Cacciatore
Francesco
F
Galizia
Gianluigi
G
Della-Morte
David
D
Rossetti
Marianna
M
Abbruzzese
Rosa
R
Langellotto
Assunta
A
Avolio
Daniela
D
Gargiulo
Gaetano
G
Ferrara
Nicola
N
Rengo
Franco
F
Abete
Pasquale
P
D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D016009:Chi-Square Distribution; D002908:Chronic Disease / Q000401:mortality*; D015897:Comorbidity; D004185:Disability Evaluation; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D009026:Mortality / Q000639:trends*; D016016:Proportional Hazards Models; D012307:Risk Factors; D012944:Social Support; D011795:Surveys and Questionnaires; D016019:Survival Analysis