Lymphedema: This condition is common in morbidly obese individuals due to impaired lymphatic drainage, which can be exacerbated by the patient's weight. The swelling is typically bilateral and can affect the fingers, hands, and arms.

Osteoarthritis: A common condition in older adults, especially those with obesity, which can cause swelling and pain in the fingers due to joint inflammation and degeneration.
Rheumatoid Arthritis: An autoimmune disorder that can cause symmetric swelling and pain in the fingers, although it's less common in new onset at 60 years old without prior symptoms.
Gout: Especially in the context of obesity, gout can cause sudden, severe swelling and pain in the fingers, typically affecting a single joint at a time.
Fluid Retention: Due to heart failure, kidney disease, or liver disease, which can be more prevalent in morbidly obese individuals, leading to generalized edema, including in the fingers.

Deep Vein Thrombosis (DVT): Although less common in the arms, DVT can cause swelling and should be considered, especially if there's a history of recent immobility, cancer, or other thrombotic risk factors.
Cellulitis or Infection: Bacterial infections of the skin and soft tissues can cause rapid onset of swelling, redness, and warmth, which requires prompt antibiotic treatment.
Thyroid Disorders: Both hypothyroidism and hyperthyroidism can cause swelling of the hands and fingers, among other systemic symptoms.

Scleroderma: A chronic autoimmune disease characterized by thickening of the skin and connective tissue, which can lead to swelling and tightening of the skin on the fingers.
Sarcoidosis: A condition that can cause inflammation in various parts of the body, including the skin, which might result in swelling of the fingers, although this is less common.
Amyloidosis: A group of diseases that can cause abnormal protein deposits in various tissues, including the skin, leading to swelling among other symptoms.