Study of hypothalamo pituitary adrenal axis in frail elderly subjects.

BACKGROUND Frail elderly people are at increased risk of death and disability from minor environmental stresses such as infection because they do not have the reserves to respond and maintain adequate homeostasis Studies have shown that elderly patients had a significantly smaller response to ACTH stimulation test. Due to paucity of data regarding HPA axis functioning in frail elderly in Indian studies, we assessed the adrenocortical response to ACTH stimulation test in frail elderly subjects. OBJECTIVES To assess the basal serum cortisol levels and serum cortisol response to 1 mcg ACTH stimulation test in frail elderly subjects. METHODOLOGY Case control study. Elderly patients visiting OPD or admitted at M.S.Ramaiah hospital from September 2007 to August 2009 were classified into 2 groups. Those fulfilling the criteria of frailty above 65 yrs were taken as cases, non frail elderly were taken as controls. 40 cases and 20 controls were included. RESULTS Equal number of hospitalized and out patient subjects were studied (20 in each group). Mean age was 75.35 years in hospitalized frails, 69.6 years in out patient frails, 68.3 years in controls. M: F ratio was 1:1. 45% of cases had frailty index of 4. A delta rise of > 9 mcg/dl (after 1 mcg ACTH stimulation test) was seen in 10 cases (25%) of frail elderly as compared to 16 controls(80%) indicating a possible adrenal insufficiency in remaining 30 cases (75%). The mean duration of hospital stay was 5.6 days. Frail elderly with poor ACTH response had poor quality of life as measured by activities of daily living score (p = .026). CONCLUSION Frail elderly individuals have adrenal insufficiency (subclinical hypocortisolemia) compared to healthy elderly subjects, thereby indicating a poorer response to ACTH stimulation test may influence outcome during acute illness. Frail elderly with poor ACTH response had poor quality of life as measured by activities of daily living score (p = .026). Hyponatremia and hypotension co related well with state of adrenal insufficiency.