Thyroid disease in cats is linked to heart disease and a fast heartbeat in conjunction with any other symptoms of thyroid problems is cause for a trip to the vet. Once the hyperthyroidism is treated, your cat's heart rate should return to normal.
Stress reaction â some studies have found that paranoia is more common in people who have experienced severe and ongoing stress â for example, prisoners of war. How stress can trigger paranoia is unclear.
When your body reacts to a physical, mental or emotional stimulus, it can cause stress that interferes with your health or normal functioning. Stress occurs when situations put more pressure on you than you think you can handle. One symptom of long-term stress is fatigue, defined as physical or mental exhaustion.