Brief answer...given below Detailed answer.... Hello, Thanks for the query. As our age advances,the function of heart starts getting influenced by decrease in elasticity of heart and atherosclerotic processes in the entire cardiovascular system. This results in increase in resistance to the pumping action of heart which makes the heart work harder to drive the blood to different organs and tissues of body. The atherosclerosis results in stiffening of arteries which tends  to raise the blood pressure. Now coming to your query of increased heart rate. If an elderly person starts having symptoms like progressive fatigue,shortness of breath,pain or discomfort in chest,fast heart beats or slow heart beats or irregular heartbeats etc may not be the consequence of age alone but could signify a recently acquired heart condition or some general condition like anemia or hyperthyroidism etc. However all these conditions carry different sign and symptoms and so it would be better for you to consult a doctor and get a comprehensive check including anaemia,hyperthyroidism,ECG,echo cardio gram and a possible coronary arteriography,if your doctor thinks so. Low body temperature could be because of low blood supply to the periphery of your body and is normal in advancing age and hence normal. I hope it helps however you may revert to me for any further query. Best of luck. Thanks

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