Kidney Stones in the Elderly

Historically kidney stones affect adults aged 20-60 years-old.  However, 10-20% of patients presenting with stones are >65 years-old and as the population ages and the older demographic increases, it is important to understand how to evaluate, treat and prevent kidney stones in this population.[1-4]  Especially as older patients have higher risk of infectious complications and overall morbidity following treatment of stones.[5]  Here we review the important epidemiology and clinical management considerations for the elderly patient with kidney stones.

Epidemiological Considerations

• Historic estimates for stone disease in the elderly were 2%; contemporary estimates are closer to 12% (which is equivalent to the general population). [6]
• 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 [8]
• 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]

Clinical Presentation 

• 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.[8]
• 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.[11]
• Hypocitraturia and hypernatriuria are the most common abnormalities in elderly men.[12]
• 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 [16]
• 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,[17] 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.[18]

Treatment Considerations for Elderly Patients

• Older patients are more likely to fail medical expulsive therapy.[13]
• 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.[27]

Elderly patients are an increasing demographic in the management of kidney stones.  These patients can present with different symptoms, different stones and metabolic abnormalities than their younger counterparts and therefore warrant different consideration when applying behavioral and medical therapies.  In addition, the morbidity profile of PCNL, ESWL and ureteroscopy is different for the older patient and while each approach is valid, the risk-benefit profile should be considered on an individual basis.

Max Kates, MD

Brian Matlaga, MD

This blog entry is extracted from "Stones in the Elderly," which appears in Current Geriatric Reports, by Max Kates and Brian Matlaga.  The entire publication is available at link.springer.com.
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.

1. Bartoletti R, Cai T, Mondaini N, et al. Epidemiology and risk factors in urolithiasis. Urol Int. 2007;79 Suppl 1:3–7. 

2. Knoll T, Schubert AB, Fahlenkamp D, Leusmann DB, Wendt-Nordahl G, Schubert G. Urolithiasis through the ages: data on more than 200,000 urinary stone analyses. J Urol. 2011;185:1304–11.

3. Usui Y, Matsuzaki S, Matsushita K, Shima M. Urolithiasis in geriatric patients. Tokai J Exp Clin Med. 2003;28:81–7.

4.Yoshida O, Terai A, Ohkawa T, Okada Y. National trend of the incidence of urolithiasis in Japan from 1965 to 1995. Kidney Int. 1999;56:1899–904.

5. Worcester E, Parks JH, Josephson MA, Thisted RA, Coe FL.Causes and consequences of kidney loss in patients with nephrolithiasis. Kidney Int. 2003;64:2204–13.

6. Gentle DL, Stoller ML, Bruce JE, Leslie SW. Geriatric urolithiasis. J Urol. 1997;158:2221–4.

7. Arampatzis S, Lindner G, Irmak F, Funk GC, Zimmermann H, Exadaktylos AK. Geriatric urolithiasis in the emergency department: Risk factors for hospitalisation and emergency management patterns of acute urolithiasis. BMC Nephrol. 2012;13:117-2369-13-117.

8. Daudon M, Dore JC, Jungers P, Lacour B. Changes in stone composition according to age and gender of patients: a multivariate epidemiological approach. Urol Res. 2004;32:241–7.

9. Heller HJ, Sakhaee K, Moe OW, Pak CY. Etiological role of estrogen status in renal stone formation. J Urol. 2002;168:1923–7.

10. Yasui T, Iguchi M, Suzuki S, et al. Prevalence and epidemiologic characteristics of lower urinary tract stones in Japan. Urology. 2008;72:1001–5.

11. Goldfarb DS, Parks JH, Coe FL. Renal stone disease in older adults. Clin Geriatr Med. 1998;14:367–81.

12. Freitas Junior CH, Mazzucchi E, Danilovic A, Brito AH, Srougi M. Metabolic assessment of elderly men with urolithiasis. Clin (Sao Paulo). 2012;67:457–61.

13. Krambeck AE, Lieske JC, Li X, Bergstralh EJ, Melton 3rd LJ, Rule AD. Effect of age on the clinical presentation of incident symptomatic urolithiasis in the general population. J Urol. 2013;189:158–64.

14. Curhan GC, Willett WC, Rimm EB, Stampfer MJ. A prospective study of dietary calcium and other nutrients and the risk of symptomatic kidney stones. N Engl J Med. 1993;328:833–8.

15. Borghi L, Meschi T, Amato F, Briganti A, Novarini A, Giannini A. Urinary volume, water and recurrences in idiopathic calcium nephrolithiasis: a 5-year randomized prospective study. J Urol. 1996;155:839–43.

16. Taylor EN, Curhan GC. Diet and fluid prescription in stone disease. Kidney Int. 2006;70:835–9.

17. Heaney RP. Calcium supplementation and incident kidney stone risk: a systematic review. J Am Coll Nutr. 2008;27:519–27.

18. Obligado SH, Goldfarb DS. The association of nephrolithiasis with hypertension and obesity: a review. Am J Hypertens. 2008;21:257–64.

19. Stoller ML, Bolton D, St Lezin M, Lawrence M. Percutaneous nephrolithotomy in the elderly. Urology. 1994;44:651–4.

20. Sahin A, Atsu N, Erdem E, et al. Percutaneous nephrolithotomy in patients aged 60 years or older. J Endourol. 2001;15:489–91.

21. Kuzgunbay B, Turunc T, Yaycioglu O, et al. Percutaneous nephrolithotomy for staghorn kidney stones in elderly patients. Int Urol Nephrol. 2011;43:639–43.

22. Kane CJ, Bolton DM, Stoller ML. Current indications for open stone surgery in an endourology center. Urology. 1995;45:218–21.

23. Matlaga BR, Assimos DG. Changing indications of open stone surgery. Urology. 2002;59:490–3. discussion 493-4.

24. Paik ML, Wainstein MA, Spirnak JP, Hampel N, Resnick MI. Current indications for open stone surgery in the treatment of renal and ureteral calculi. J Urol. 1998;159:374–8. discussion 378-9.

25. Sighinolfi MC, Micali S, Grande M, Mofferdin A, De Stefani S, Bianchi G. Extracorporeal shock wave lithotripsy in an elderly population: how to prevent complications and make the treatment safe and effective. J Endourol. 2008;22:2223–6.

26. Philippou P, Lamrani D, Moraitis K, Bach C, Masood J, Buchholz N. Is shock wave lithotripsy efficient for the elderly stone formers? Results of a matched-pair analysis. Urol Res. 2012;40:299–304.

27. Aboumarzouk OM, Kata SG, Keeley FX, Nabi G. Extracorporeal shock wave lithotripsy (ESWL) versus ureteroscopic management for ureteric calculi. Cochrane Database Syst Rev. 2011;(12):CD006029.