Aerobic training in older adults with type 2 diabetes and vasodepressive carotid sinus hypersensitivity.

BACKGROUND AND AIMS: Vasodepressive carotid sinus hypersensitivity (V-CSH) is a common but incurable etiology for fainting in older adults with diabetes (OADM), and is diagnosed by carotid sinus massage (CSM). Aerobic exercise has been shown to be an effective therapy for other neuroautonomic etiologies of syncope (such as orthostatic hypotension), but the effectiveness of aerobic training in V-CSH remains unknown. We examined whether aerobic training could attenuate the vasodepressive response to CSM in OADM (older adults with type 2 diabetes) subjects complicated by V-CSH. METHODS: Forty OADM subjects (mean age 72.2 ± 0.7) complicated by V-CSH were recruited. Subjects were randomized to each of two groups: an aerobic group (AT, n = 20, 3 months vigorous aerobic exercise), and a nonaerobic (NA, n = 20, no aerobic exercise) group. Exercise sessions were supervised by a certified exercise trainer three times per week. The vasodepressive response [defined as the decrease in systolic blood pressure (SBP) during CSM] was measured before and after the training intervention using a Finometer. RESULTS: The intervention had no impact on the number of subjects that met the criteria for V-CSM in either the AT or NA groups, regardless of the criteria used (-10, -20, -30, -40 and -50 mmHg). There was no training effect on the vasodepressive response in either the AT or NA group (P = 0.214, 2-way analysis of variance, -30 mmHg definition for V-CSH). CONCLUSIONS: Aerobic training has no effect on the SBP response to CSM in OADM subjects with V-CSH. Unlike in other neuroautonomic etiologies for fainting, aerobic exercise is not effective as a treatment for V-CSH, at least in the OADM population.

Short-term aerobic exercise reduces nitroglycerin-induced orthostatic intolerance in older adults with type 2 diabetes.

AIMS/HYPOTHESIS: Older adults are at a high risk for syncope due to orthostatic intolerance (OI), and this risk increases with comorbid type 2 diabetes and vasoactive medications. Despite many benefits, previous investigations have shown worsening OI with aerobic training. We examined whether aerobic exercise reduced OI in older adults with type 2 diabetes who were given a short-acting vasoactive agent (nitroglycerin). METHODS: Forty older adults (25 males and 15 females, mean age 71.4 ± 0.7 years, ranging in age from 65 to 83 years) with type 2 diabetes were recruited. Subjects were randomized to each of 2 groups: an aerobic group (3 months of vigorous aerobic exercise) and a nonaerobic (no aerobic exercise) group. Exercise sessions were supervised by a certified exercise trainer 3 times per week. After being given 400 µg of sublingual nitroglycerin, each subject was placed in a 70° head-up tilt for 30 minutes. RESULTS: When the 2 groups were compared using a Cox proportional hazards model, tilt table tolerance was significantly better in the aerobic group as compared to in the nonaerobic group (χ(2)(MC) = 7.271, P = 0.007). CONCLUSIONS: Our findings indicate that a relatively short aerobic exercise intervention can improve postnitroglycerin orthostatic tolerance in older adults with type 2 diabetes.

Aerobic training restores arterial baroreflex sensitivity in older adults with type 2 diabetes, hypertension, and hypercholesterolemia.

OBJECTIVE: Lowered baroreflex sensitivity (BRS) predicts mortality and occurs with increasing age and diabetes. We examined whether aerobic exercise could restore arterial BRS in adults at high cardiovascular risk (diabetes, geriatric age group, hypercholesterolemia, and hypertension). DESIGN: Randomized, controlled, single-blind study. SETTING: VITALiTY (Vancouver Initiative to Add Life to Years) Research Laboratory. PARTICIPANTS: Thirty-nine older adults (mean age, 71.5 +/- 0.7 years) with diet-controlled or oral hypoglycemic-controlled type 2 diabetes, hypertension, and hypercholesterolemia. INTERVENTIONS: Subjects were recruited to each of 2 groups: an aerobic group (3 months of vigorous aerobic exercise as defined by 80% to 85% of maximal heart rate), and a nonaerobic (no aerobic exercise) group. Exercise sessions were supervised by a certified exercise trainer 3 times per week. MAIN OUTCOME MEASURES: : Baroreflex function was assessed using the spontaneous baroreflex method. Main outcome measures included BRS, BRS(up), BRS(down), and [latin capital V with dot above]o(2)max. RESULTS: The aerobic group demonstrated an increase in BRS that was not demonstrated in the nonaerobic group (+60.9 +/- 23.5 vs +2.2 +/- 7.9%; P = 0.010). CONCLUSIONS: Our findings indicate that a relatively short aerobic exercise intervention can reverse functional impairments of the arterial baroreflex function in older adults at high cardiovascular risk.

Short-term aerobic exercise reduces arterial stiffness in older adults with type 2 diabetes, hypertension, and hypercholesterolemia.

OBJECTIVE The relationship between increased arterial stiffness and cardiovascular mortality is well established in type 2 diabetes. We examined whether aerobic exercise could reduce arterial stiffness in older adults with type 2 diabetes complicated by comorbid hypertension and hyperlipidemia. RESEARCH DESIGN AND METHODS A total of 36 older adults (mean age 71.4 +/- 0.7 years) with diet-controlled or oral hypoglycemic-controlled type 2 diabetes, hypertension, and hypercholesterolemia were recruited. Subjects were randomly assigned to one of two groups: an aerobic group (3 months vigorous aerobic exercise) and a nonaerobic group (no aerobic exercise). Exercise sessions were supervised by a certified exercise trainer three times per week, and a combination of cycle ergometers and treadmills was used. Arterial stiffness was measured using the Complior device. RESULTS When the two groups were compared, aerobic training resulted in a decrease in measures of both radial (-20.7 +/- 6.3 vs. +8.5 +/- 6.6%, P = 0.005) and femoral (-13.9 +/- 6.7 vs. +4.4 +/- 3.3%, P = 0.015) pulse-wave velocity despite the fact that aerobic fitness as assessed by Vo(2max) did not demonstrate an improvement with training (P = 0.026). CONCLUSIONS Our findings indicate that a relatively short aerobic exercise intervention in older adults can reduce multifactorial arterial stiffness (type 2 diabetes, aging, hypertension, and hypercholesterolemia).