- Department of Neurosurgery, Center for Neurosurgical Outcomes Research, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center 8631 W. Third Street, Suite 800E, Los Angeles, CA 90048, USA
Department of Neurosurgery, Center for Neurosurgical Outcomes Research, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center 8631 W. Third Street, Suite 800E, Los Angeles, CA 90048, USA
DOI:10.4103/2152-7806.110023Copyright: © 2013 Dickinson H This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
How to cite this article: Dickinson H, Carico C, Miriam Nuño, Nosova K, Elramsisy A, Patil CG. The effect of weight in the outcomes of meningioma patients. Surg Neurol Int 03-Apr-2013;4:45
How to cite this URL: Dickinson H, Carico C, Miriam Nuño, Nosova K, Elramsisy A, Patil CG. The effect of weight in the outcomes of meningioma patients. Surg Neurol Int 03-Apr-2013;4:45. Available from: http://sni.wpengine.com/surgicalint_articles/the-effect-of-weight-in-the-outcomes-of-meningioma-patients/
Background:Meningiomas are more prevalent in women and mostly benign in nature. Our aim was to evaluate the association of weight and outcomes of meningioma patients undergoing craniotomy.
Methods:A retrospective analysis of meningioma patients discharged postcraniotomy between 1998 and 2007 was conducted. Univariate and multivariate analysis evaluated in-hospital mortality, complications, length of stay (LOS), and cost.
Results:According to the nationwide inpatient sample (NIS) database, an estimated 72,257 adult meningioma patients underwent a craniotomy in US hospitals during the study period. Female and male weight loss rates were 0.7% and 1.2%, respectively; obesity rates were 5.2% and 3.7%. Males had higher rates of malignant tumors than females (6.2% vs. 3.5%, P P = 0.03). Weight loss was associated with higher mortality in men (OR 6.66, P P = 0.04) as well as higher rates of postoperative complications in both men (OR 6.13, P P P = 0.0006) and complications (OR 0.8, P = 0.0007) among women.
Conclusions:In summary, weight loss seems to be the single most critical factor present in patients experiencing higher mortality, complications, hospital charges, and longer LOS. However, further studies aimed to assess the inter-relation of potential preexisting comorbidities and weight loss are needed to establish causation.
Keywords: Complications, craniotomy, hospitalization cost, length of stay, meningioma, mortality, obesity, weight loss
Meningiomas are the second most common primary neoplasm of the central nervous system and are mostly (90%) of benign nature. Incidence is approximated at about 209 per 100,000 people in the United States,[
Besides the implicated risk of gender for meningiomas, previous studies identified obesity as a potential comorbidity associated with increased risk of postoperative complications, particularly in men.[
Using the Nationwide Inpatient Sample (NIS) database, we analyze the outcomes of adult meningioma patients that underwent a craniotomy between 1998 and 2007. Data was obtained from the Healthcare Cost and Utilization Project of the Agency for Healthcare Research and Quality (HCUP). The NIS contains discharge data on 100% of discharges from a sample of hospitals that are selected for inclusion into the database using a stratified random sampling technique. This produces a representative 20% sub-sample of all United States nonfederal hospital discharges, so that conclusions drawn from the database can be confidently generalized to the entire United States medical community. Because the NIS contains data on all patients discharged from sampled hospitals during a given year regardless of age or payer status, it can be used to obtain an annual total volume of specified procedures at individual hospitals. This study was deemed as exempt from review by the Cedars-Sinai Institutional Review Board.
Inclusion and exclusion criteria for cases analyzed
Data was queried to include adult patients (≥18 years) with a primary diagnosis of meningioma (ICD-9-CM diagnosis codes 225.2, 192.1, 237.6), principal procedure of craniotomy (ICD-9-CM procedure code 01.51). Principal diagnosis code is assumed as the condition primarily responsible for the patient's need for treatment as deemed by the admitting physician.[
Patient and hospital characteristics
A patient's age, gender, race, median household income, primary insurance payer (e.g., medicare, medicaid, private), type of admission (e.g., emergency, urgent, elective), discharge disposition (e.g., routine, transfer, home health care, died), hospital type (teaching vs. nonteaching), in-hospital length of stay (LOS), and total charges were extracted from the NIS database. Race was categorized into Caucasian versus all other. Missing rates for race and admission source variables were 35% and 2%, respectively. An Elixhauser, et al.[
Primary outcomes of interest
Mortality, postsurgical complications, in-hospital LOS, and total charges were evaluated. NIS captures mortality as a binary outcome (death or alive), LOS in days, and total charges (dollars) as continuous variables. Postoperative complications consistent with a craniotomy included the following: Postoperative fluid and electrolyte abnormalities (276.0-276.9), cerebrospinal fluid rhinorrhea (349.81), pulmonary (518.81-518.85, 997.3), stroke (253.5, 998.11, 997.02), cardiac (410, 997.1), thromboembolic complications including deep venous thrombosis and pulmonary embolism (415, 387, 415.11-415.19, 451.0-451.9, 453.0-453.9), postoperative neurologic including those due to infarction or hemorrhage (997.00-997.09), hematoma (998.1-998.13), and hydrocephalus or ventriculostomy (331.3-331.4).
Descriptive statistics and multivariate analysis adjusted for weight loss, obesity, and potentially confounding factors. Adjusted Odds ratio (OR), 95% confidence intervals (CI), and corresponding P values were reported in all relevant analyses. Estimations to the entire US population were performed using the SAS PROC SURVEY methodology. All analysis was conducted using SAS version 9.1 for Windows (SAS Institute Inc., Cary, NC).
A total of 72,257 meningioma patients underwent a craniotomy between 1998 and 2007 [
Weight loss and tumor characteristics
Overall, meningiomas in females were 95.9% benign, 3.5% malignant, and 0.6% of uncertain behavior [
Weight loss and complications
In a sub-analysis of weight loss and obesity, we found that weight status was associated with increased rates of certain complications, yet decreased rates of others [
Multivariate analysis of outcomes
Female gender (OR 0.85, CI: 0.75-0.97, P = 0.02), higher hospital volume (OR 0.98, CI: 0.98-0.99, P < 0.0001) and obesity (OR 0.47, CI: 0.30-0.72, P < 0.0001) were associated with decreased risk of in-hospital mortality [
Older age and ER admission were significant predictors of postoperative complications in women and men [
Since length of hospital stay and cost are likely to be affected by a patient's survival status, these outcomes were analyzed while considering the survivors.
Age, race, admission source surgery delay, and number of procedures had a similar effect on LOS and cost independently of gender. Weight loss increased LOS by 2.3 and 3.2 days in women and men, respectively. Obesity reduced LOS in women by 0.3 days while having no effect in the LOS in men. Postoperative complications increased LOS in men more significantly than in women. For instance, thromboembolic, neurological, postoperative fluid complications, and pulmonary increased LOS in women by 3.6, 3.6, 1.6, and 1.3 days and in men by 4.3, 4.0, 2.5, and 2.4 days, respectively.
Total charges were similar in women in men by age, race, admissions source, surgery delay, and number of procedures as observed in LOS [
A total of 72,257 adult meningioma patients underwent craniotomy for resection of meningioma between 1998 and 2007; 70% were female and overall average age was 58 years. Women had shorter hospital stays and lower mortality than men. Higher rates of malignant tumors were found in patients with weight loss (6.4% vs. 3.0%). Weight loss alone was associated with a 9% increased rate of mortality in females and 20% increased rate in males.
In previous studies, comorbidities along with patient-level and tumor-specific characteristics have been found to be significantly associated with the outcomes of neurosurgical patients.[
An important consideration regarding the observed risk of poor outcome in patients suffering weight loss may be explained by the fact that weight loss is associated with potentially confounding factors such as preexisting conditions (as opposed to acting in causation of them), and it is rather these comorbidities ultimately affecting patient outcomes. To this end, our current study adjusted for comorbidities such as diabetes, hypertension, coagulopathy, renal failure, and others, however, further studies are needed to decipher the potential relationship of weight loss with these comorbidities as well as others. Further explanation includes the fact that the complications selected for analyses were not all-encompassing and influenced outcomes of our statistical models, or that weight loss stemmed from malnutrition in direct result of these complications.
Obesity has long been an accepted risk factor associated with poor outcomes in patients undergoing surgery. However, recent studies regarding the prognostic effect of obesity yielded mixed conclusions.[
Within the field of neurosurgery very few studies have investigated the role of obesity in patient outcomes. These previous studies have shown higher levels of mortality and complication in both solely male obese and mixed male and female obese meningioma patient cohorts.[
The strengths of this study lie in its ability to assess the effect of weight at a large scale, which permits critical gender-specific explorations. However, there are also several limitations in this study that should be considered in future explorations. Obesity as coded in the NIS database does not involve severity levels, which is likely to be essential in understanding the association of obesity in the outcomes of patients. Future studies of obesity should involve BMI as an improved measure of obesity. Given the obesity rates found in this study and recently increasing rates of obesity in the US, it is very likely that NIS data underestimates obesity. Unlike obesity, however, weight loss as coded in the NIS seems to involve fewer limitations. Lastly, our study is limited is that it can only assess short-term outcomes such as mortality and complications, however, future studies should also involve long-term outcomes such as hospital readmissions, overall survival and postdischarge complications, to name a few.
In congruence with the previously cited studies, our data emphasizes weight loss rather than obesity seems to be associated with poor outcomes among meningioma patients undergoing a craniotomy. Potentially explaining this result is that weight loss may be considered a proxy for malnutrition, a condition resulting in poor homeostasis. Patients experiencing preoperative weight loss have less nutritional reserve then patients who are overweight or mildly obese.[
Based on the results of our study, weight status appears to be associated with both mortality and postoperative morbidity. Our findings show that factors such as weight loss, admission source, and specific postoperative complications are critical in determining cost and resource utilization burden in the care of meningioma patients undergoing a craniotomy. Our results emphasize the need for systematic assessment of weight loss history and nutritional status in all meningioma patients under consideration for craniotomy, especially in the context of alternative, less invasive treatment options such as radiosurgery. Furthermore, although obesity has long been considered a significant surgical risk factor, the results of our study demonstrate that this may not necessarily be the case, as in our cohort no obese men experienced death and the odds of mortality was less in obese women. Future studies that are able to take into account the severity of obesity may shed more light on the complex relationship between obesity and postsurgical meningioma patient outcomes.
1. Aghi MK, Eskandar EN, Carter BS, Curry WT, Barker FG. Increased prevalence of obesity and obesity-related postoperative complications in male patients with meningiomas. Neurosurgery. 2007. 61: 754-60
2. Last accessed on 2011 Nov. Available from: http://www.cancer.org/Research/CancerFactsFigures/index Available from: http://www.cbtrus.org/2002/2002report.pdf 2012 .
3. Carmichael AR. Obesity as a risk factor for development and poor prognosis of breast cancer. BJOG. 2006. 113: 1160-6
4. Carroll RS, Zhang J, Black PM. Expression of estrogen receptors alpha and beta in human meningiomas. J Neurooncol. 1999. 42: 109-16
5. Davenport DL, Xenos ES, Hosokawa P, Radford J, Henderson WG, Endean ED. The influence of body mass index obesity status on vascular surgery 30-day morbidity and mortality. J Vasc Surg. 2009. 49: 140-7
6. Dindo D, Muller MK, Weber M, Clavien PA. Obesity in general elective surgery. Lancet. 2003. 361: 2032-5
7. Elixhauser A, Steiner C, Harris DR, Coffey RM. Comorbidity measures for use with administrative data. Med Care. 1998. 36: 8-27
8. Gregg JR, Cookson MS, Phillips S, Salem S, Chang SS, Clark PE. Effect of preoperative nutritional deficiency on mortality after radical cystectomy for bladder cancer. J Urol. 2011. 185: 90-6
9. Hsu DW, Efird JT, Hedley-Whyte ET. Progesterone and estrogen receptors in meningiomas: Prognostic considerations. J Neurosurg. 1997. 86: 113-20
10. Kamat AM, Shock RP, Naya Y, Rosser CJ, Slaton JW, Pisters LL. Prognostic value of body mass index in patients undergoing nephrectomy for localized renal tumors. Urology. 2004. 63: 46-50
11. Meijer K, de Vries M, Al-Lahham S, Bruinenberg M, Weening D, Dijkstra M. Human primary adipocytes exhibit immune cell function: Adipocytes prime inflammation independent of macrophages. PLoS One. 2011. 6: e17154-
12. Moiyadi AV, Shetty PM. Perioperative outcomes following surgery for brain tumors: Objective assessment and risk factor evaluation. J Neurosci Rural Pract. 2012. 3: 28-35
13. Mullen JT, Davenport DL, Hutter MM, Hosokawa PW, Henderson WG, Khuri SF. Impact of body mass index on perioperative outcomes in patients undergoing major intra-abdominal cancer surgery. Ann Surg Oncol. 2008. 15: 2164-72
14. .editors. Organization WHO. International classification of diseases and related health problems. Geneva: 1993. p.
15. Rabadán AT, Hernandez D, Eleta M, Pietrani M, Baccanelli M, Christiansen S. Factors related to surgical complications and their impact on the functional status in 236 open surgeries for malignant tumors in a Latino-American hospital. Surg Neurol. 2007. 68: 412-20
16. Rajaraman P. Hunting for the causes of meningioma: Obesity is a suspect. Cancer Prev Res (Phila). 2011. 4: 1353-5
17. Roelvink NC, Kamphorst W, van Alphen HA, Rao BR. Pregnancy-related primary brain and spinal tumors. Arch Neurol. 1987. 44: 209-15
18. Schneider B, Pülhorn H, Röhrig B, Rainov NG. Predisposing conditions and risk factors for development of symptomatic meningioma in adults. Cancer Detect Prev. 2005. 29: 440-7
19. Schoenberg BS, Christine BW, Whisnant JP. Nervous system neoplasms and primary malignancies of other sites. The unique association between meningiomas and breast cancer. Neurology. 1975. 25: 705-12
20. Speirs V, White MC, Green AR. Collagenase III: A superior enzyme for complete disaggregation and improved viability of normal and malignant human breast tissue. In vitro Cell Dev Biol Anim. 1996. 32: 72-4
21. van Venrooij LM, de Vos R, Borgmeijer-Hoelen MM, Haaring C, de Mol BA. Preoperative unintended weight loss and low body mass index in relation to complications and length of stay after cardiac surgery. Am J Clin Nutr. 2008. 87: 1656-61