- Historic estimates for stone disease in the elderly were 2%; contemporary estimates are closer to 12% (which is equivalent to the general population). 
- Elderly patients are more likely to have bladder stones (due to benign prostatic hyperplasia and obstructive symptoms in men).
- Stone size, laterality, location and recurrence rates do not vary with age.[3,7]
- Among all age groups, men are two to three times more likely than women to develop kidney stones.
- Male predominance is most pronounced in middle-aged men (2.8x for age 5-59).
- Male predominance decreases with age:
- 2.49x compared to women for age 60-69
- 2.23x for age 70-79
- 1.8x for age 80-89
- 1.6x for age 90 or greater 
- Estrogens are known to have a protective effect on the formation of kidney stones and hypothesized to explain the narrowing of the gender-gap in post-menopausal age range.[9,10]
- Struvite and uric acid stones are more common in older patients calcium and cysteine stones are less common.
- Calcium stones: >80% of stones in patients 20-60 years-old; <50% in patients >80.
- Struvite stones: 2% age <30 years-old; >30% in patients >80.[3,8]
- The most common metabolic profile in older patients is hypercalciuria, however elderly patients secrete less calcium than younger patients.
- Hypocitraturia and hypernatriuria are the most common abnormalities in elderly men.
- Elderly patients are more likely to:
- present without symptoms or with atypical symptoms (fever, pyuria, diarrhea).
- have multiple comorbidities
- have urinary tract infections and bacteremia
- be hospitalized (2x)
- Elderly patients are less likely to receive pain medications or medications for medical expulsive therapy.[7,13]
Preventive Therapies and Dietary Modifications in the Elderly
- For elderly patients, low urine output and low fluid intake may contribute to stone formation.
- Increased fluid intake (goal 2L urine daily) may lower the incidence of stone formation and decrease recurrence rates.[14,15]
- To combat the hypocitraturia and hypernatriuria common in elderly men, decreasing salt and protein intake while increasing citrate intake will promote a balanced intracellular pH.
- Vitamin C supplementation increases the risk of kidney stones in older men; compared to men who take <90mg/day:
- men who take 250-500mg/day have a 20% increased risk of stones
- men who take >1000mg/day have a 40% increased risk 
- Many elderly patients have osteopenia and osteoporosis for which they take calcium supplementation.
- It is well established that a diet of increased calcium and restricted animal protein and sodium decreases recurrence rates in known stone-formers, however routinely checking 24-hour urinalyses may help balance the risks of bone disease and kidney stone formation.
- Weight reduction is a non-age-specific intervention that is proven to reduce stone formation.
Treatment Considerations for Elderly Patients
- Older patients are more likely to fail medical expulsive therapy.
- Complication rates of percutaneous nephrolithotomy (PCNL) can be significant and morbid in the elderly.
- Transfusion rates were higher in the elderly, but have declined among all age groups over the past 20 years.[19-21]
- Stone-free rates are similar among all age groups undergoing PCNL.[22-24]
- Extracorporeal Shock Wave Lithotripsy (ESWL) has a 52-71% stone clearance rate in the elderly with low rates of major complications.[25,26]
- Ureteroscopy and laser lithotripsy has a higher stone-free rate but higher complication rate in the elderly.
|Max Kates, MD|
|Brian Matlaga, MD|
Max Kates, MD is a resident at the Brady Urological Institute at Johns Hopkins. Brian Matlaga, MD, is an Associate Professor of Urology, Director of Stone Disease and Director of Ambulatory Care at the Brady Urological Institute at Johns Hopkins.