An older man shakes when he ties his shoelaces. He has started to buy clothing with zippers because he can no longer do up small buttons. This man may be suffering from

Shaking, or tremor, along with increasing difficulty performing small, precise movements such as fastening buttons, can be signs of Parkinson’s disease. Parkinson’s affects movement and coordination, which can make everyday tasks harder. Alzheimer’s primarily affects memory and thinking, while lupus and stroke do not best fit this gradual pattern of tremor and fine-motor difficulty.

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