There are several medical conditions to which people with McArdle disease are more prone than the rest of the population.
High muscle glycogen concentrations in skeletal muscle  or a sedentary lifestyle may contribute.
Due to high level of purine metabolism, possibly leading to gout and/or renal calculi  (page 11).
Obesity (and all its ill effects)
Many are overweight, contributed to by the avoidance of activity due to associated painful cramping if not guided correctly .
Depression and anxiety
Factors include living with a chronic condition and worry about severe episodes and the need for hospitalization.
Some cases of rhabdomyolysis lead to acute renal failure (page 9). However, chronic renal disease is not reported to be associated.
Data suggests that McArdle’s does not significantly increase the risk of complications for pregnancy and delivery . Anecdotal evidence shows symptoms being reduced during pregnancy.
Like anyone else, people with McArdle’s may develop other diseases. Care should be taken to properly investigate and not assume that reported symptoms are due to the patient’s McArdle disease.
 Decreased insulin action in skeletal muscle from patients with McArdle’s disease. Nielsen JN, Vissing J, Wojtaszewski JF, Haller RG, Begum N, Richter EA. (2002) Am J Physiol Endocrinol Metab. Jun;282(6):E1267-75.
 McArdle’s disease and gout. Puig JG, de Miguel E, Mateos FA, Miranda E, Romera NM, Espinos A, and Gijon J (1992) Muscle Nerve 15: 822-828.
 McArdle Disease: a clinical review. Quinlivan R, Buckley J, James M et al. (2009) J Neurol Neurosurg Psychiatry. https://doi: 10.1136/jnnp.2009.195040.
McArdle Disease Medical Overview