Abstract
Summary
The literature is limited regarding risk factors for acute kidney injury (AKI) and mortality in hip fracture patients, although AKI is common in these patients. While obese patients were at increased risk of AKI, underweight patients with and without AKI had elevated mortality for up to 1 year after hip fracture surgery, compared with normal-weight patients.
Introduction
This study aimed to examine risk of postoperative AKI and subsequent mortality, by body mass index (BMI) level, in hip fracture surgery patients aged 65 and over.
Methods
A regional cohort study using medical databases was used. We included all patients who underwent surgery to repair a hip fracture during the years 2005–2011 (n = 13,529) at hospitals in Northern Denmark. We calculated cumulative risk of AKI by BMI level during 5 days postsurgery and subsequent short-term (6–30 days postsurgery) and long-term (31–365 days post-surgery) mortality. We calculated crude and adjusted hazard ratios (aHRs) for AKI and death with 95% confidence intervals (CIs), comparing underweight, overweight, and obese patients with normal-weight patients.
Results
Risks of AKI within five postoperative days were 11.9, 10.1, 12.5, and 17.9% for normal-weight, underweight, overweight, and obese patients, respectively. Among those who developed AKI, short-term mortality was 14.1% for normal-weight patients compared to 23.1% for underweight (aHR 1.7 (95% CI 1.2–2.4)), 10.7% for overweight (aHR 0.9 (95% CI 0.6–1.1)), and 15.2% for obese (aHR 0.9 (95% CI 0.6–1.4)) patients. Long-term mortality was 24.5% for normal-weight, 43.8% for underweight (aHR 1.6 (95% CI 1.0–2.6)), 20.5% for overweight (aHR 0.8 (95% CI 0.6–1.2)), and 21.4% for obese (aHR 1.1 (95% CI 0.7–1.8) AKI patients. Similar associations between BMI and mortality were observed among patients without postoperative AKI, although the absolute mortality risk estimates by BMI were considerably lower in patients without than in those with AKI.
Conclusions
Obese patients were at increased risk of AKI compared with normal-weight patients. Among patients with and without postoperative AKI, overweight and obesity were not associated with mortality. Compared to normal-weight patients, underweight patients had elevated mortality for up to 1 year after hip fracture surgery irrespective of the presence of AKI. The absolute mortality risks were higher in all BMI groups with the presence of AKI.
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References
Kanis JA, Oden A, McCloskey EV, Johansson H, Wahl DA, Cooper C (2012) A systematic review of hip fracture incidence and probability of fracture worldwide. Osteoporos Int 23:2239–2256
Nielsen KA, Jensen NC, Jensen CM, Thomsen M, Pedersen L, Johnsen SP, Ingeman A, Bartels PD, Thomsen RW (2009) Quality of care and 30 day mortality among patients with hip fractures: a nationwide cohort study. BMC Health Serv Res 9:186
Lawrence VA, Hilsenbeck SG, Noveck H, Poses RM, Carson JL (2002) Medical complications and outcomes after hip fracture repair. Arch Intern Med 162:2053–2057
Roche JJ, Wenn RT, Sahota O, Moran CG (2005) Effect of comorbidities and postoperative complications on mortality after hip fracture in elderly people: prospective observational cohort study. BMJ 331:1374
Pedersen AB, Christiansen CF, Gammelager H, Kahlert J, Sorensen HT (2016) Risk of acute renal failure and mortality after surgery for a fracture of the hip: a population-based cohort study. Bone Joint J 98-B:1112–1118
Flegal KM, Carroll MD, Kit BK, Ogden CL (2012) Prevalence of obesity and trends in the distribution of body mass index among US adults, 1999-2010. JAMA 307:491–497
Billings FT, Pretorius M, Schildcrout JS, Mercaldo ND, Byrne JG, Ikizler TA, Brown NJ (2012) Obesity and oxidative stress predict AKI after cardiac surgery. J Am Soc Nephrol 23:1221–1228
Kelz RR, Reinke CE, Zubizarreta JR, Wang M, Saynisch P, Even-Shoshan O, Reese PP, Fleisher LA, Silber JH (2013) Acute kidney injury, renal function, and the elderly obese surgical patient: a matched case-control study. Ann Surg 258:359–363
Wolf BR, Lu X, Li Y, Callaghan JJ, Cram P (2012) Adverse outcomes in hip arthroplasty: long-term trends. J Bone Joint Surg Am 94:e103
Ulucay C, Eren Z, Kaspar EC, Ozler T, Yuksel K, Kantarci G, Altintas F (2012) Risk factors for acute kidney injury after hip fracture surgery in the elderly individuals. Geriatr Orthop Surg Rehabil 3:150–156
Hsu CY, McCulloch CE, Iribarren C, Darbinian J, Go AS (2006) Body mass index and risk for end-stage renal disease. Ann Intern Med 144:21–28
Calle EE, Thun MJ, Petrelli JM, Rodriguez C, Heath CW Jr (1999) Body-mass index and mortality in a prospective cohort of U.S. adults. N Engl J Med 341:1097–1105
Manson JE, Willett WC, Stampfer MJ, Colditz GA, Hunter DJ, Hankinson SE, Hennekens CH, Speizer FE (1995) Body weight and mortality among women. N Engl J Med 333:677–685
Barba R, Zapatero A, Losa JE, Valdes V, Todoli JA, Di MP, Monreal M (2008) Body mass index and mortality in patients with acute venous thromboembolism: findings from the RIETE registry. J Thromb Haemost 6:595–600
Park J, Ahmadi SF, Streja E, Molnar MZ, Flegal KM, Gillen D, Kovesdy CP, Kalantar-Zadeh K (2014) Obesity paradox in end-stage kidney disease patients. Prog Cardiovasc Dis 56:415–425
Silva HG, Mendonca LM, Conceicao FL, Zahar SE, Farias ML (2007) Influence of obesity on bone density in postmenopausal women. Arq Bras Endocrinol Metabol 51:943–949
Vemmos K, Ntaios G, Spengos K, Savvari P, Vemmou A, Pappa T, Manios E, Georgiopoulos G, Alevizaki M (2011) Association between obesity and mortality after acute first-ever stroke: the obesity-stroke paradox. Stroke 42:30–36
Curtis JP, Selter JG, Wang Y, Rathore SS, Jovin IS, Jadbabaie F, Kosiborod M, Portnay EL, Sokol SI, Bader F, Krumholz HM (2005) The obesity paradox: body mass index and outcomes in patients with heart failure. Arch Intern Med 165:55–61
Escalante A, Haas RW, del Rincon I (2005) Paradoxical effect of body mass index on survival in rheumatoid arthritis: role of comorbidity and systemic inflammation. Arch Intern Med 165:1624–1629
Pickkers P, de KN, Dusseljee J, Weerheijm D, van der Hoeven JG, Peek N (2013) Body mass index is associated with hospital mortality in critically ill patients: an observational cohort study. Crit Care Med 41:1878–1883
Sorensen HT (1997) Regional administrative health registers as a resource in clinical epidemiology. A study of options, strenghts, limitations and data quality provided with examples of use. Int J Risk Safety Med 10:1–22
Frank L (2000) Epidemiology. When an entire country is a cohort. Science 287:2398–2399
WHO (1995) Physical status: the use and interpretation of anthropometry. Report of a WHO expert committee. WHO technical report series 854. World Health Organization. 1995, Geneva
Danish Hip fracture database (2015) Annual report 2014
Grann AF, Erichsen R, Nielsen AG, Froslev T, Thomsen RW (2011) Existing data sources for clinical epidemiology: the clinical laboratory information system (LABKA) research database at Aarhus University, Denmark. Clin Epidemiol 3:133–138
International Union for Pure and Applied Chemistry (2013). http://www.iupac.org/
Go AS, Parikh CR, Ikizler TA, Coca S, Siew ED, Chinchilli VM, Hsu CY, Garg AX, Zappitelli M, Liu KD, Reeves WB, Ghahramani N, Devarajan P, Faulkner GB, Tan TC, Kimmel PL, Eggers P, Stokes JB (2010) The assessment, serial evaluation, and subsequent sequelae of acute kidney injury (ASSESS-AKI) study: design and methods. BMC Nephrol 11:22
Bellomo R, Ronco C, Kellum JA, Mehta RL, Palevsky P (2004) Acute renal failure—definition, outcome measures, animal models, fluid therapy and information technology needs: the second international consensus conference of the acute dialysis quality initiative (ADQI) group. Crit Care 8:R204–R212
Kidney Disease: Improving Global Outcomes (KDIGO) Acute Kidney Injury Work Group (2012) KDIGO clinical practice guideline for acute kidney injury. Kidney International Supplements 2:1–138
Schmidt M, Pedersen L, Sorensen HT (2014) The Danish civil registration system as a tool in epidemiology. Eur J Epidemiol 29:541–549
Charlson ME, Pompei P, Ales KL, MacKenzie CR (1987) A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis 40:373–383
de Groot V, Beckerman H, Lankhorst GJ, Bouter LM (2003) How to measure comorbidity. A critical review of available methods. J Clin Epidemiol 56:221–229
Levey AS, Eckardt KU, Tsukamoto Y, Levin A, Coresh J, Rossert J, De ZD, Hostetter TH, Lameire N, Eknoyan G (2005) Definition and classification of chronic kidney disease: a position statement from kidney disease: improving global outcomes (KDIGO). Kidney Int 67:2089–2100
Johannesdottir SA, Horvath-Puho E, Ehrenstein V, Schmidt M, Pedersen L, Sorensen HT (2012) Existing data sources for clinical epidemiology: the Danish National Database of reimbursed prescriptions. Clin Epidemiol 4:303–313
Ranstam J, Karrholm J, Pulkkinen P, Makela K, Espehaug B, Pedersen AB, Mehnert F, Furnes O (2011) Statistical analysis of arthroplasty data. II. Guidelines. Acta Orthop 82:258–267
Carpenter J, Kenward M (2013) Multiple imputation and its application
Jafari SM, Huang R, Joshi A, Parvizi J, Hozack WJ (2010) Renal impairment following total joint arthroplasty: who is at risk? J Arthroplast 25:49–53, 53
Takahashi K, Nammour TM, Fukunaga M, Ebert J, Morrow JD, Roberts LJ, Hoover RL, Badr KF (1992) Glomerular actions of a free radical-generated novel prostaglandin, 8-epi-prostaglandin F2 alpha, in the rat. Evidence for interaction with thromboxane A2 receptors. J Clin Invest 90:136–141
Brienza N, Giglio MT, Marucci M, Fiore T (2009) Does perioperative hemodynamic optimization protect renal function in surgical patients? A meta-analytic study. Crit Care Med 37:2079–2090
Sinclair S, James S, Singer M (1997) Intraoperative intravascular volume optimisation and length of hospital stay after repair of proximal femoral fracture: randomised controlled trial. BMJ 315:909–912
Piccoli A, Brunani A, Savia G, Pillon L, Favaro E, Berselli ME, Cavagnini F (1998) Discriminating between body fat and fluid changes in the obese adult using bioimpedance vector analysis. Int J Obes Relat Metab Disord 22:97–104
James MT, Grams ME, Woodward M, Elley CR, Green JA, Wheeler DC, de JP, Gansevoort RT, Levey AS, Warnock DG, Sarnak MJ (2015) A meta-analysis of the Association of Estimated GFR, albuminuria, diabetes mellitus, and hypertension with acute kidney injury. Am J Kidney Dis 66:602–612
Choban PS, Flancbaum L (1997) The impact of obesity on surgical outcomes: a review. J Am Coll Surg 185:593–603
Bihorac A, Yavas S, Subbiah S, Hobson CE, Schold JD, Gabrielli A, Layon AJ, Segal MS (2009) Long-term risk of mortality and acute kidney injury during hospitalization after major surgery. Ann Surg 249:851–858
Henegar JR, Bigler SA, Henegar LK, Tyagi SC, Hall JE (2001) Functional and structural changes in the kidney in the early stages of obesity. J Am Soc Nephrol 12:1211–1217
Brandstrup B, Tonnesen H, Beier-Holgersen R, Hjortso E, Ording H, Lindorff-Larsen K, Rasmussen MS, Lanng C, Wallin L, Iversen LH, Gramkow CS, Okholm M, Blemmer T, Svendsen PE, Rottensten HH, Thage B, Riis J, Jeppesen IS, Teilum D, Christensen AM, Graungaard B, Pott F (2003) Effects of intravenous fluid restriction on postoperative complications: comparison of two perioperative fluid regimens: a randomized assessor-blinded multicenter trial. Ann Surg 238:641–648
Choban PS, Heckler R, Burge JC, Flancbaum L (1995) Increased incidence of nosocomial infections in obese surgical patients. Am Surg 61:1001–1005
Bouillanne O, Dupont-Belmont C, Hay P, Hamon-Vilcot B, Cynober L, Aussel C (2009) Fat mass protects hospitalized elderly persons against morbidity and mortality. Am J Clin Nutr 90:505–510
Kvamme JM, Holmen J, Wilsgaard T, Florholmen J, Midthjell K, Jacobsen BK (2012) Body mass index and mortality in elderly men and women: the Tromso and HUNT studies. J Epidemiol Community Health 66:611–617
Weiss A, Beloosesky Y, Boaz M, Yalov A, Kornowski R, Grossman E (2008) Body mass index is inversely related to mortality in elderly subjects. J Gen Intern Med 23:19–24
Mahan KL, Escott-Stump S, Raymond JL (2011) Krauses’s Food and the Nutrition Care Process, 13th edn
Mainz J, Krog BR, Bjornshave B, Bartels P (2004) Nationwide continuous quality improvement using clinical indicators: the Danish National Indicator Project. Int J Qual Health Care 16(Suppl 1):i45–i50
Mokdad AH, Marks JS, Stroup DF, Gerberding JL (2004) Actual causes of death in the United States, 2000. JAMA 291:1238–1245
Acknowledgements
The authors wish to thank the orthopedic surgeons and other healthcare professionals at all hospitals in Denmark for their cooperation in submitting data to Danish national registries. The study was supported by a grant from Aarhus University Research Foundation and by the Program for Clinical Research Infrastructure (PROCRIN), established by the Lundbeck Foundation and the Novo Nordisk Foundation.
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This study was approved by the Danish Data Protection Agency (record number 2013-41-1924). As the study did not involve any contact with patients or any intervention, it was not necessary to obtain permission from the Danish Scientific Ethical Committee.
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Pedersen, A.B., Gammelager, H., Kahlert, J. et al. Impact of body mass index on risk of acute kidney injury and mortality in elderly patients undergoing hip fracture surgery. Osteoporos Int 28, 1087–1097 (2017). https://doi.org/10.1007/s00198-016-3836-8
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DOI: https://doi.org/10.1007/s00198-016-3836-8