IFSO Worldwide Survey 2016: Primary, Endoluminal, and Revisional Procedures

BACKGROUND AND AIM

The International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO), being a Federation of 62 national societies, is the ideal network to monitor the number and type of procedures at a global level. The IFSO survey, enriched with a special section on revisional procedures, aims to report the number and types of bariatric procedures performed worldwide in 2016 and analyzes the surgical trends from 2008 to 2016.

METHODS

The 2016 IFSO Survey form was emailed to all IFSO societies. Each Society was requested to indicate the number and type of bariatric procedures performed in the country. Trend analyses from 2008 to 2016 were also performed.

RESULTS

The total number of bariatric/metabolic procedures performed in 2016 was 685,874; 634,897 (92.6%) of which were primary and 50,977 were revisional (7.4%). Among the primary interventions, 609,897 (96%) were surgical and 25,359 (4%) were endoluminal. The most performed primary surgical bariatric/metabolic procedure was sleeve gastrectomy (SG) (N = 340,550; 53.6%), followed by Roux-en-Y gastric bypass (N = 191,326; 30.1%), and one-anastomosis gastric bypass (N = 30,563; 4.8%).

CONCLUSIONS

In 2016, there was an increase in the total number both of surgical and endoluminal bariatric/metabolic procedures. Revisional procedures represent about 7% of the total bariatric interventions. SG remains the most performed surgical procedure in the world.

Bariatric Surgery and Endoluminal Procedures: IFSO Worldwide Survey 2014

BACKGROUND AND AIM

Several bariatric surgery worldwide surveys have been previously published to illustrate the evolution of bariatric surgery in the last decades. The aim of this survey is to report an updated overview of all bariatric procedures performed in 2014.For the first time, a special section on endoluminal techniques was added.

METHODS

The 2014 International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) survey form evaluating the number and the type of surgical and endoluminal bariatric procedures was emailed to all IFSO societies. Trend analyses from 2011 to 2014 were also performed.

RESULTS

There were 56/60 (93.3%) responders. The total number of bariatric/metabolic procedures performed in 2014 consisted of 579,517 (97.6%) surgical operations and 14,725 (2.4%) endoluminal procedures. The most commonly performed procedure in the world was sleeve gastrectomy (SG) that reached 45.9%, followed by Roux-en-Y gastric bypass (RYGB) (39.6%), and adjustable gastric banding (AGB) (7.4%). The annual percentage changes from 2013 revealed the increase of SG and decrease of RYGB in all the IFSO regions (USA/Canada, Europe, and Asia/Pacific) with the exception of Latin/South America, where SG decreased and RYGB represented the most frequent procedure.

CONCLUSIONS

There was a further increase in the total number of bariatric/metabolic procedures in 2014 and SG is currently the most frequent surgical procedure in the world. This is the first survey that describes the endoluminal procedures, but the accuracy of provided data should be hopefully improved in the next future. We encourage the creation of further national registries and their continuous updates taking into account all new bariatric procedures including the endoscopic procedures that will obtain increasing importance in the near future.

Bariatric Surgery and Endoluminal Procedures: IFSO Worldwide Survey 2014

BACKGROUND AND AIM

Several bariatric surgery worldwide surveys have been previously published to illustrate the evolution of bariatric surgery in the last decades. The aim of this survey is to report an updated overview of all bariatric procedures performed in 2014.For the first time, a special section on endoluminal techniques was added.

METHODS

The 2014 International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) survey form evaluating the number and the type of surgical and endoluminal bariatric procedures was emailed to all IFSO societies. Trend analyses from 2011 to 2014 were also performed.

RESULTS

There were 56/60 (93.3%) responders. The total number of bariatric/metabolic procedures performed in 2014 consisted of 579,517 (97.6%) surgical operations and 14,725 (2.4%) endoluminal procedures. The most commonly performed procedure in the world was sleeve gastrectomy (SG) that reached 45.9%, followed by Roux-en-Y gastric bypass (RYGB) (39.6%), and adjustable gastric banding (AGB) (7.4%). The annual percentage changes from 2013 revealed the increase of SG and decrease of RYGB in all the IFSO regions (USA/Canada, Europe, and Asia/Pacific) with the exception of Latin/South America, where SG decreased and RYGB represented the most frequent procedure.

CONCLUSIONS

There was a further increase in the total number of bariatric/metabolic procedures in 2014 and SG is currently the most frequent surgical procedure in the world. This is the first survey that describes the endoluminal procedures, but the accuracy of provided data should be hopefully improved in the next future. We encourage the creation of further national registries and their continuous updates taking into account all new bariatric procedures including the endoscopic procedures that will obtain increasing importance in the near future.

Bariatric Surgery Worldwide 2013

BACKGROUND

The first global survey of bariatric/metabolic surgery based on data from the nations or national groupings of the International Federation for the Surgery of Obesity and Metabolic Diseases (IFSO) was published in 1998, followed by reports in 2003, 2009, 2011, and 2012. In this survey, we report a global overview of worldwide bariatric surgery in 2013.

MATERIALS AND METHODS

A questionnaire evaluating the number and the type of bariatric procedure performed in 2013 was emailed to all members of bariatric societies belonging to IFSO. Trend analyses from 2003 to 2013 were also performed.

RESULTS

There were 49/54 (90.7%) responders; 37 of the 49 with national registries. The total number of bariatric procedures performed worldwide in 2013 was 468,609, 95.7% carried out laparoscopically. The highest number (n = 154,276) was from the USA/Canada region. The most commonly performed procedure in the world was Roux-en-Y gastric bypass (RYGB), 45%; followed by sleeve gastrectomy (SG), 37%; and adjustable gastric banding (AGB), 10%. Most significant were the rise in prevalence of SG from 0 to 37% of the world total from 2003 to 2013, and the fall in AGB of 68% from its peak in 2008 to 2013.

CONCLUSIONS

SG is currently the most frequently performed procedure in the USA/Canada and in the Asia/Pacific regions, and second to RYGB in the Europe and Latin/South America regions. The accuracy of the IFSO-based world survey of procedures would be enhanced if each nation or national group would create a national registry.

Inter-disciplinary European guidelines on surgery of severe obesity

In 2005, for the first time in European history, an extraordinary Expert panel named 'The BSCG' (Bariatric Scientific Collaborative Group), was appointed through joint effort of the major European Scientific Societies which are active in the field of obesity management. Societies that constituted this panel were: IFSO - International Federation for the Surgery of Obesity, IFSO-EC - International Federation for the Surgery of Obesity - European Chapter, EASO - European Association for Study of Obesity, ECOG - European Childhood Obesity Group, together with the IOTF (International Obesity Task Force) which was represented during the completion process by its representative. The BSCG was composed not only of the top officers representing the respective Scientific Societies (four acting presidents, two past presidents, one honorary president, two executive directors), but was balanced with the presence of many other key opinion leaders in the field of obesity. The BSCG composition allowed the coverage of key disciplines in comprehensive obesity management, as well as reflecting European geographical and ethnic diversity. This joint BSCG expert panel convened several meetings which were entirely focused on guidelines creation, during the past two years. There was a specific effort to develop clinical guidelines, which will reflect current knowledge, expertise and evidence based data on morbid obesity treatment.

Plasma lipids and cardiovascular risk: a POSCH report. Program on the Surgical Control of the Hyperlipidemias

Quantifying the relationship between changes in lipid variables and clinical endpoints has been difficult. We studied the predictive value of various lipid variables on three endpoints in the Program on the Surgical Control of the Hyperlipidemias (POSCH): overall mortality, coronary heart disease (CHD) mortality, and CHD mortality and confirmed nonfatal myocardial infarction (MI) combined. We measured lipid variables for the annual visits from baseline to 5 years for actual follow-up values, actual and percentage differences between baseline and follow-up values, as well as the parameters comparing baseline only to 5 years for actual differences, percentage differences, and the ratio of baseline to 5 years. The lipid variables included were total cholesterol, low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, very low density lipoprotein (VLDL) cholesterol, triglycerides, and the LDL cholesterol/HDL cholesterol ratio. The analytic method used was that of Cox regression, with age and sex as secondary covariates, and each lipid or ratio of lipids as the primary (univariate) covariate. As a result, 108 univariate Cox regressions were conducted. The combined findings for the control and the intervention groups are presented. The number of events for the combined group were: overall mortality, 190; CHD mortality, 119; and CHD mortality and confirmed nonfatal MI, 262. The highest hazard ratios were found for the lipid variable of the LDL cholesterol/HDL cholesterol ratio (e.g. 1.196 for a 1-unit increase). Only for the combined endpoint of CHD mortality and confirmed nonfatal MI was there a substantial number of statistically significant relationships (P<0.01) of lipid variables and parameters of assessment.

Effect of plasma cholesterol on red blood cell oxygen transport

1. Oxygen (O2) transfer from the blood to tissues is a function of the red blood cell (RBC) O2 saturation (SO2), the plasma O2 content being negligible. Under conditions of increased tissue O2 demand, the SO2 of arterial blood does not change appreciably (97%); however, the SO2 of mixed venous blood, equal to that of the perfused tissues, can go as low as 20%. 2. Tissue O2 availability is limited by the exposure time to a RBC, which decreases under conditions of maximum stress (< 1 s). If the O2 unloading time was to increase significantly, because of a decrease in the RBC diffusion constant or an increase in the RBC membrane thickness, the RBC O2 unloading time would exceed tissue (e.g. cardiac) transit time and O2 transfer would be impaired. 3. Cholesterol constitutes the non-polar, hydrophobic lipid of the enveloping layer of the RBC membrane. As the cholesterol content of the RBC increases, the fluidity of the membrane decreases and the lipid shell stiffens. 4. Early studies demonstrated that high blood cholesterol concentrations were associated with reduced blood O2 transport; in essence, the haemoglobin dissociation curve was shifted to the left. 5. Current investigations have shown that the cholesterol RBC membrane barrier to O2 diffusion delayed O2 entry into the RBC during saturation and delayed O2 release from the RBC during desaturation. In an analysis of 93 patients divided by their cholesterol concentration into five groups, the percentage change in blood O2 diffusion was inversely proportional to the cholesterol concentration. 6. The RBC membrane cholesterol is in equilibrium with the plasma cholesterol concentration. It stands to reason that as the plasma cholesterol increases, the RBC membrane becomes impaired and O2 transport is reduced. 7. The implications of this new perspective on O2 transport include the ability to increase tissue oxygenation by lowering plasma cholesterol.

Plasma cholesterol: an influencing factor in red blood cell oxygen release and cellular oxygen availability

BACKGROUND

A fairly immediate reduction in angina pectoris symptoms after cholesterol lowering has been described. Our previous findings in rabbits and in a four-patient human pilot study indicated the existence of an RBC membrane barrier to oxygen (O2) transport in the presence of hypercholesterolemia. Our current objective was to determine whether, and to what extent, the plasma cholesterol concentration is an influencing factor in RBC O2 release and cellular O2 availability.

STUDY DESIGN

In an unique O2 diffusion analysis system, blood samples from 100 patients referred for lipid modification were analyzed. After 1 to 2 minutes of mixing in our diffusion analysis system, the next 1 to 2 minutes of circulation is comparable with 1 to 2 seconds of myocardial capillary flow. RBC O2 diffusion was defined by the depletion rate of total O2 content in blood from full O2 saturation (98%) to desaturation (approximately 60%). Relative tissue O2 availability was defined as the percentage decrease in O2 availability between the high-cholesterol group and the low-cholesterol group.

RESULTS

The 100 patients were divided almost equally into two groups on the basis of plasma cholesterol ranges of 175 to 229 mg/dL (n=49) and 230 to 299 mg/dL (n = 51). The mean cholesterol concentrations and percentage increases in the high-cholesterol group over the low-cholesterol group were: for plasma, 206 +/- 0.3 and 256 +/- 0.4 mg/dL, 24.3% (p < 0.001); for RBCs, 93 +/- 0.2 and 106 +/- 0.2mg/dL, 14.0% (p < 0.001); and for RBC membranes, 41 +/- 0.1 and 54 +/- 0.2mg/dL, 31.7% (p < 0.001). The blood O2 diffusion curves were distinctly different between the high- and the low-cholesterol groups (p < 0.05). Blood O2 diffusion, defined by the blood O2 diffusion curves, was inversely proportional to the plasma, RBC, and RBC-membrane cholesterol concentrations. The relative tissue O2 availability, after a circulation period of more than 3 minutes in the diffusion system, showed a decrease of 17.5% (p < 0.05) between the plasma cholesterol groups. In comparing the two plasma cholesterol concentration extremes of less than 200mg/dL (n= 14) and greater than 275 mg/dL (n= 11) after a circulation period of more than 3 minutes in the diffusion system, we found a decrease in relative tissue O2 availability of 35.8% (p < 0.05).

CONCLUSIONS

The plasma cholesterol concentration may be an influencing factor in RBC-membrane cholesterol content, which, in turn, may regulate RBC-membrane O2 transport, RBC O2 release, and cellular O2 availability. The implications of this work include the addition of angina pectoris control to the indications for appropriate lipid modification and the development of an in vitro blood stress test to replace patient cardiac stress testing.

A novel device for measuring the effect of cholesterol on the release of oxygen from red blood cells into myocardial tissue

A novel method has been devised to measure the effect of cholesterol on the release of oxygen (O2) from the red blood cell (RBC) into a tailored environment, which can be made to mimic myocardial tissue. Cholesterol affects the cell membrane of the RBC and thus the release of O2 into tissue. While this is true of all tissue, the myocardium is especially sensitive because of its critical nature, its high O2 requirements, and the shortness of time that arterial blood spends in the muscle. Calculations are presented that show that the release time for O2 from RBCs is close to the residence time of the RBC in the coronary system. Sequential measurements of blood oxygen saturation (SO2) are made when oxygenated blood is subjected to conditions similar to those in the myocardium. The natural logarithm of the relative value of the SO2 at time t compared with the initial value of the SO2 can be fitted to a straight line whose slope is proportional to the parameters of the RBC membrane, the sample size, the hematocrit, and the diffusion parameters of the apparatus. This value is used to estimate the effects of cholesterol-lowering treatments on O2 release. This test will serve as a valuable adjunct to or replacement for stress tests in the evaluation of coronary artery disease, especially in patients whose physical conditions make standard stress testing painful or risky.

Decreased blood oxygen diffusion in hypercholesterolemia

BACKGROUND

Improvement of angina pectoris symptoms after cholesterol lowering has raised questions as to the underlying mechanisms.

METHODS

Rabbit experiment: We compared arterial blood samples from New Zealand White cholesterol-supplemented rabbits (n = 6) with nonsupplemented rabbit samples (n = 4) in a closed-loop circulation diffusion system. The pH and partial pressures of oxygen (pO2) and carbon dioxide (pCO2) were measured continuously. The samples were first oxygen (O2) saturated (pO2, 160 mm Hg; pCO2, 4 mm Hg) and then desaturated in 100% nitrogen. Cholesterol levels were determined in whole blood, plasma (P Chol), red blood cells (RBCs), and RBC membranes. Human experiment: We exposed quadruple desaturated venous blood samples (n = 4) with P Chol levels of 87 to 400 mg/dL in a gas exchanger to capillary gas conditions (pO2, 23 mm Hg; pCO2, 46 mm Hg). After 15 minutes we performed blood gas analyses and compared our results to baseline values.

RESULTS

In the rabbit experiment the cholesterol-supplemented group as compared to the control group showed higher plasma pO2 levels during the saturation phase and lower plasma pO2 levels during the desaturation phase. It also had a markedly increased RBC membrane cholesterol content: 121 +/- 3 (standard error of the mean [SEM]) mg/dL versus 22 +/- 1.7 mg/dL in the control group (P < .05). This barrier to RBC membrane O2 diffusion caused delayed O2 entry into the RBCs during saturation, with a higher plasma pO2, and delayed O2 release from the RBCs during desaturation, with a lower plasma pO2. In the human experiment the P Chol level was inversely correlated with the percentage change of O2 content in milliliters of O2 per deciliter of blood (P < .05).

CONCLUSIONS

Increased RBC membrane cholesterol in hypercholesterolemia appears to decrease the transmembrane O2 diffusion rate.

Effective lipid modification by partial ileal bypass reduced long-term coronary heart disease mortality and morbidity: five-year posttrial follow-up report from the POSCH. Program on the Surgical Control of the Hyperlipidemias

BACKGROUND

In 1990, when the Program on the Surgical Control of the Hyperlipidemias (POSCH) reported its in-trial results strongly supporting the conclusion that effective lipid modification reduces progression of atherosclerosis, the differences for the end points of overall mortality and mortality from atherosclerotic coronary heart disease (ACHD) did not reach statistical significance.

METHODS

The Program on the Surgical Control of the Hyperlipidemias recruited men and women with a single documented myocardial infarction between the ages of 30 and 64 years who had a plasma cholesterol level higher than 5.69 mmol/L (220 mg/dL) or higher than 5.17 mmol/L (200 mg/dL) if the low-density lipoprotein cholesterol level was in excess of 3.62 mmol/L (140 mg/dL). Between 1975 and 1983, 838 patients were randomized: 417 to the diet control group and 421 to the diet plus partial ileal bypass intervention group. Mean patient follow-up for this 5-year posttrial report was 14.7 years (range, 12.2-20 years).

RESULTS

At 5 years after the trial, statistical significance was obtained for differences in overall mortality (P = .049) and mortality from ACHD (P = .03). Other POSCH end points included overall mortality (left ventricular ejection fraction > or =50%) (P = .01), mortality from ACHD (left ventricular ejection fraction > or =50%) (P = .05), mortality from ACHD and confirmed nonfatal myocardial infarction (P<.001), confirmed nonfatal myocardial infarction (P<.001), mortality from ACHD, confirmed and suspected myocardial infarction and unstable angina (P<.001), incidence of coronary artery bypass grafting or percutaneous transluminal coronary angioplasty (P<.001), and onset of clinical peripheral vascular disease (P = .02). There were no statistically significant differences between groups for cerebrovascular events, mortality from non-ACHD, and cancer. All POSCH patients have been available for follow-up.

CONCLUSION

At 5 years after the trial, all POSCH mortality and atherosclerosis end points, including overall mortality and mortality from ACHD, demonstrated statistically significant differences between the study groups.

Myocardial infarction and percent arteriographic stenosis of culprit lesion: report from the Program on the Surgical Control of the Hyperlipidemias (POSCH)

The objective of this study was to assess the percent stenosis of the culprit lesion responsible for subsequent myocardial infarction in the Program on the Surgical Control of the Hyperlipidemias (POSCH). It is unknown if the susceptible coronary artery culprit lesion responsible for an acute myocardial infarction is relatively large ( > or = 50% arteriographic stenosis) and hemodynamically significant ( > or = 70% stenosis), or small ( < 50%, stenosis) and asymptomatic. Certain necropsy and arteriography studies support the large progenitor lesion concept, and other arteriography studies support the small lesion hypothesis. We analyzed the coronary arteriogram immediately preceding a Q wave (transmural) myocardial infarction for the degree of stenosis of the suspected culprit lesion, which was selected by visual inspection of the coronary circulation supplying the electrocardiogram-defined area of myocardial infarction. There was no perceptible difference with respect to vessel segment distribution of culprit lesions or time to infarction between the 52 control-group patients and the 27 intervention-group patients. For the two groups combined (n=79), the predominantly involved segments were the middle right coronary artery and the proximal left anterior descending coronary artery. The time interval from the preceding coronary arteriogram closest to the index myocardial infarction ranged from 0 days to 10 years; however, 64.6% of the arteriograms were performed 2 years or less prior to the myocardial infarction. Only 5.1% of the patients in both groups combined had a culprit lesion stenosis < 50%, while 88.6% of the patients in both groups combined had a culprit lesion stenosis > or = 70%. The results strongly favor the large lesion hypothesis of causation for myocardial infarction. It is premature, however, to state that the relative size of the culprit lesion has been indisputably determined. The resolution of this problem has exceedingly important practical implications for the management of patients with known atherosclerotic coronary heart disease and for those asymptomatic individuals with silent atherosclerotic coronary heart disease.

Three helpful techniques for facilitating abdominal procedures, in particular for surgery in the obese

Three helpful techniques for facilitating abdominal procedures, in particular in the obese, are presented. Midline abdominal exposure is aided by the manual separation of the subcutaneous fat and Scarpa's fascia by a lateral tearing motion simultaneously performed from opposite sides of the table. Exposure of the upper abdomen is best achieved by utilization of a fixed-support retractor system placed with the patient in the Trendelenburg position, followed by positioning the patient in the reverse Trendelenburg position for the conduct of the operation. Ventral hernia repair is promoted when the three mobile layers of anterior rectus sheath, rectus muscle, and posterior rectus sheath are approximated with a continuous suture to create a neo-linea alba.

Surgical procedures and devices should be evaluated in the same way as medical therapy

This paper is a personal essay that starts and ends with the message that surgical procedures and devices should be evaluated in the same way as medical therapies, namely, by randomized clinical trials (RCTs). I discuss, with particular attention to surgical procedures and devices, the objections raised against RCTs in medical decision-making, a schema for utilizing the traditional phases of RCTs in the evaluation of surgical procedures and devices, the importance of RCTs to FDA approval, financial compensation, and health care costs, the impact of RCTs on clinical practice, the role of RCTs in academia, teaching, and research, and the surgeon's obligation to participate in a leadership role in RCTs. The belief is expressed that national funding of health care should mandate allocations for RCTs and that such expenditures, as well as the spending of health care dollars on the basis of the outcomes of such trials, will not only improve patient management in the shortest time but will eventually reduce health care costs. The RCT, by selecting effective and safe surgical procedures and devices, as well as diets and drugs, is the best means science has to assess the validity of patient management.

Iron and atherosclerosis: inhibition by the iron chelator deferiprone (L1)

BACKGROUND

Accumulating evidence suggests that oxidative modification of lipoproteins may play a significant role in atherogenesis. In this study, we hypothesized that the iron chelator deferiprone (L1) would function as an antioxidant and decrease atherosclerosis progression.

MATERIALS AND METHODS

For the in vitro studies, human low-density lipoprotein (LDL) was collected and then subjected to oxidation by either hemin/H2O2 or copper sulfate in the presence of various concentrations of L1. Lag time to oxidation was measured to assess antioxidant activity of L1. In addition, human umbilical vein endothelial cells (HUVEC) were subjected to oxidized LDL in the presence of varying concentrations of L1 to assess the antioxidant cytoprotective ability of L1. For the in vivo studies, rabbits (n = 21) were maintained on a 0.25% by weight cholesterol diet for 10 weeks; 9 rabbits also received twice daily L1 by gavage (total dose = 100 mg/kg/day). Lipid profiles were measured during the study. At 10 weeks, rabbits were sacrificed, and thoracic aorta cholesterol content (TACC) and planimetry were determined to assess atherosclerosis severity.

RESULTS

In vitro, L1 prevented oxidation of LDL and protected HUVEC from the cytotoxic effects of oxidized LDL in a concentration-dependent manner. In vivo, L1 reduced TACC (P = 0.001), while also significantly decreasing total plasma cholesterol (P = 0.003), very-low-density lipoprotein cholesterol (P = 0.01), and LDL cholesterol (P = 0.002) compared to control animals. However, no significant differences between L1-treated animals and controls were evident for the surface area of plaque involvement by planimetry (P = 0.3) or in the serum iron levels (P = 0.3).

CONCLUSIONS

These results confirm that L1 possesses antioxidant activity in vitro and may reduce atherogenesis in vivo.

Gastric obesity surgery combined with partial ileal bypass for hypercholesterolemia

BACKGROUND

It is unusual for a patient to manifest both morbid obesity and hyperlipidemia. Certain of these individuals may also have a history of hypertriglyceridemic pancreatitis. We report six morbidly obese hypercholesterolemic patients, two with recurrent hypertriglyceridemic pancreatitis, who were managed by concurrent gastric restrictive surgery and a partial ileal bypass operation.

METHODS

The first dual procedure was performed on January 6 1992, and the most recent on February 20 1997. Our series consists of two males and four females, with an average age of 35.5 years at the time of surgery. The mean preoperative weight of these patients was 116.8 kg, and the mean BMI was 39.7 kg/m2. The preoperative mean total plasma cholesterol was 5.5 g/l and the mean plasma triglyceride was 30.61 g/l; the two patients with a history of hypertriglyceridemic pancreatitis had plasma triglyceride levels of 33.6 g/l and 65 g/l.

RESULTS

The average weight reduction, using available follow-up intervals was 40.3 kg (34.5%), with a mean postoperative BMI of 20.0 kg/m2 (34.8% reduction). The markedly elevated total plasma cholesterol and plasma triglyceride levels were normalized, with a postoperative mean total plasma cholesterol of 1.47 g/l (73.3% reduction) and a concomitant mean plasma triglyceride of 1.63 g/l (94.7% reduction). The two patients with a history of pancreatitis sustained triglyceride reductions of 96.5% and 94.1%, and neither patient has had an episode of pancreatitis following the dual operative procedures.

CONCLUSION

We conclude that the combination of a gastric restrictive operation with a partial ileal bypass procedure represents excellent management for patients with both morbid obesity and hypercholesterolemia, especially if the hypercholesterolemia is accompanied by hypertriglyceridemic pancreatitis.

Impact of cholesterol reduction on peripheral arterial disease in the Program on the Surgical Control of the Hyperlipidemias (POSCH)

BACKGROUND

Few lipid/atherosclerosis intervention trials have assessed the impact of cholesterol reduction on peripheral arterial disease. The 838 patients evaluated in the Program on the Surgical Control of the Hyperlipidemias (POSCH) trial represent more than the total number of patients in the seven previously reported studies.

METHODS

Peripheral arterial disease in POSCH was assessed by progression of clinical disease, serial changes in the systolic blood pressure ankle/brachial index (ABI), and changes on sequential peripheral arteriograms.

RESULTS

At the time of formal closure of the POSCH trial on July 19, 1990, claudication or limb-threatening ischemia was exhibited in 72 of 417 control group (CG) patients and in 54 of 421 intervention group (IG) patients (IG relative risk [RR] 0.702, 95% confidence interval [CI] 0.169 to 1.000, p = 0.049). With additional follow-up evaluation to September 30, 1994, clinical peripheral arterial disease was evident in 91 CG patients and 64 IG patients (RR 0.656, 95% CI 0.200 to 0.903, p = 0.009). At the 5-year follow-up evaluation, an ABI of less than 0.95 was present in 41 of 120 CG patients and in 24 of 126 IG patients, all of whom had an ABI of 0.95 or greater at baseline (RR in the IG of 0.557, 95% CI 0.360 to 0.863, p < 0.01). No appreciable differences were noted in the progression or regression of arteriographic peripheral arterial disease between the two groups.

CONCLUSIONS

Effective cholesterol reduction in POSCH led to statistically significant differences between the control and the intervention groups in the development of clinically evident peripheral arterial disease and in the ABI values, but not in the peripheral arteriograms. Additional studies need to assess the correlation between peripheral arterial changes and coronary arterial changes and clinical atherosclerosis events. Intervention trials that study peripheral arterial disease have intrinsic value in the evaluation of the impact of risk factor modification on progression of atherosclerotic peripheral arterial disease.

Gender-based mortality follow-up from the Program on the Surgical Control of the Hyperlipidemias (POSCH) and meta-analysis of lipid intervention trials. Women in POSCH and other lipid trials

OBJECTIVE

The authors assessed the clinical results of lipid-lowering therapy in women.

SUMMARY BACKGROUND DATA

The Program on the Surgical Control of the Hyperlipidemias (POSCH) has demonstrated that effective lowering of total cholesterol and low-density lipoprotein cholesterol in a postmyocardial infarction population significantly reduces atherosclerotic coronary heart disease (ACHD) mortality, ACHD mortality combined with a new confirmed nonfatal myocardial infarction, and the number of coronary artery bypass grafting and angioplasty procedures performed.

METHODS

A review and meta-analysis were performed of the seven primary or secondary lipid/ atherosclerosis intervention trials-including POSCH-published in the English-language literature that included women and published results in women separate from the results in men or in the entire trial population. The main outcome measure analyzed was overall mortality.

RESULTS

The Scottish Physicians Clofibrate Study, the Newcastle upon Tyne Clofibrate Study, and the Pravastatin Limitation of Atherosclerosis in the Coronary Arteries (PLAC I) Trial may have demonstrated a possible benefit in ACHD prognosis from effective lipid intervention in women. The other four available trials did not. The Minnesota Coronary Survey reported a 15.6% increase in overall mortality rate and a 30.6% increase in a combined cardiovascular endpoint rate in the lipid-intervention group. The Upjohn Colestipol Study demonstrated statistically significant reductions in overall and ACHD mortality in the men, but not in the women. The Scandinavian.

The effect of lovastatin on [3H]thymidine uptake in HTC-4 and LLC-L1 tumor cells

Lovastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, has been shown to inhibit the in vitro and in vivo growth of a number of different cell lines. However, the mechanism by which lovastatin exerts its effect is not clear. In this experiment, we investigated the effect of lovastatin on the incorporation of [3H]thymidine by Hepatoma Tissue Culture-4 (HTC-4) and Lewis Lung Carcinoma L-1 (LLC-L1) tumor cells. Tumor cells were grown under standard conditions and treated with four different concentrations of lovastatin. Cell growth was evaluated by daily hemacytometer cell counts. On Day 4, the plates were pulsed with 10 microCi [3H]thymidine. After 24 hr, the plates were harvested and [3H]thymidine incorporation was measured by scintillation counting. Lovastatin inhibited both HTC-4 and LLC-L1 cell growth in a dose-dependent manner. At the highest lovastatin dose, both LLC-L1 and HTC-4 cell growth was slowed to less than 15% of control. Remarkably, however, both cell lines showed a paradoxical, dose related, increase in [3H]thymidine uptake. Cell cycle analysis using flow cytometry was performed on Day 5 in the LLC-L1 cell line. As the lovastatin concentration increased, a lower percentage of cells was found in the G1 phase of the cell cycle and a higher percentage of cells was found in the S and G2 phases. These findings suggest that these tumor cells are undergoing brisk DNA repair or that lovastatin is more effectively blocking cell division than cellular DNA replication.

Disease-free intervals after partial ileal bypass in patients with coronary heart disease and hypercholesterolemia: report from the Program on the Surgical Control of the Hyperlipidemias (POSCH)

OBJECTIVES

We sought to analyze the disease-free intervals and calculate the freedom from atherosclerosis events in the Program on the Surgical Control of the Hyperlipidemias (POSCH).

BACKGROUND

The POSCH study was a randomized, secondary lipid/atherosclerosis intervention trial that provided strong evidence for reduction in atherosclerosis progression as demonstrated by clinical and arteriographic end points. The 417 control group patients received American Heart Association phase II diet instruction, and the 421 intervention group patients received identical dietary instruction and underwent a partial ileal bypass operation.

METHODS

Four outcome measures were determined: 1) overall mortality, 2) coronary heart disease mortality, 3) coronary heart disease mortality and confirmed nonfatal myocardial infarction, and 4) coronary/cardiac interventions.

RESULTS

An overall mortality rate of 10% occurred at 6.7 years in the control group and 9.4 years in the intervention group, for a gain in disease-free interval of 2.7 years in the intervention group (p = 0.032). A coronary heart disease mortality rate of 8% occurred at 7.2 years in the control group and 11 years in the intervention group, for a gain of 3.8 years (p = 0.046). Twenty percent of patients demonstrated the combined end point of coronary heart disease mortality and confirmed nonfatal myocardial infarction at 5.9 years in the control group and 11.4 years in the intervention group, for a gain of 5.5 years (p < 0.001). Twenty-five percent of patients underwent either coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty or heart transplantation at 5.4 years in the control group and 12.4 years in the intervention group, for a gain of 7 years (p < 0.001).

CONCLUSIONS

The marked lipid modification achieved by partial ileal bypass in the POSCH trial led to demonstrable increases in the disease-free intervals for overall mortality, coronary heart disease mortality, coronary heart disease mortality and confirmed nonfatal myocardial infarction, and coronary intervention procedures. For the clinician and the patient, estimation of disease-free intervals may be more relevant than assessment of differences in incidence rates and risk ratios.

Effect of lovastatin alone and as an adjuvant chemotherapeutic agent on hepatoma tissue culture-4 cell growth

BACKGROUND

Cholesterol is essential for cell viability and growth. Interference with the cholesterol biosynthetic pathway with a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (e.g., lovastatin) may preferentially slow malignant cell growth and offer a new approach to cancer chemotherapy. To test this hypothesis, we evaluated the effect of lovastatin alone, and as an adjuvant chemotherapeutic agent, on the growth and function of hepatoma tissue culture-4 (HTC-4) cells.

METHODS

HTC-4 cells were treated with lovastatin at concentrations of 1, 3, 5, and 10 microM, with mitomycin-C at concentrations of 10, 25, 50, and 100 nM, or with combinations of the two drugs. Cell growth was evaluated by daily cell counts and substrate adhesion to fibronectin.

RESULTS

Lovastatin alone slowed HTC-4 cell growth at concentrations as low as 1 microM (p < 0.01). Mitomycin-C alone slowed HTC-4 cell growth at concentrations of 25 nM and above (p < 0.01). Lovastatin added to mitomycin-C-treated cells resulted in a significant adjuvant effect, with cell growth slowed by an additional 20-30% by 1 microM lovastatin and by an additional 43-63% by 5 microM lovastatin, compared to mitomycin-C alone (p < 0.01). Lovastatin-treated cells also exhibited decreased adherence to substrate (p < 0.05).

CONCLUSIONS

Lovastatin is effective alone and as an adjuvant to mitomycin-C in slowing the growth of HTC-4 cells. These in vitro results support further investigation of lovastatin as an adjuvant chemotherapeutic agent in animal models.

Effect of aspirin use on death and recurrent myocardial infarction in current and former cigarette smokers. Program on the Surgical Control of the Hyperlipidemias Group

The purpose of this study was to examine the effects of aspirin use on mortality and morbidity rates in a subset of the control group of the Program on the Surgical Control of the Hyperlipidemias (POSCH) that was stratified by cigarette smoking status at the time of randomization. The clinical impact of aspirin intake in cigarette smokers and former cigarette smokers has not been well studied. POSCH was a randomized, controlled, clinical trial designed to ascertain the effects of lipid modification by the partial ileal bypass operation on clinical end-points and arteriographic changes in postmyocardial infarction subjects with hypercholesterolemia. Cohorts of cigarette smokers in the diet-control group were evaluated for overall and atherosclerotic coronary heart disease (ACHD) mortality rates and recurrent confirmed nonfatal myocardial infarction rates. In current cigarette smokers at baseline (n = 90) with a mean follow-up of 8.3 years, the overall mortality rate was 45.2% in patients with no aspirin use and 10.4% in patients who reported even infrequent aspirin use (relative risk = 4.3, 95% confidence interval (CI) = 2.4 to 10.6, p < 0.001). For ACHD mortality in this cohort, the relative risk was 17.1 (35.7% vs 2.1%, 95% CI = 1.4 to 125.0, p < 0.001); for the combined end-point of ACHD mortality and nonfatal myocardial infarction, the relative risk was 2.4 (40.5% vs 16.7%, 95% CI = 1.2 to 5.1, p = 0.018).(ABSTRACT TRUNCATED AT 250 WORDS)

Subgroup analyses of the major clinical endpoints in the Program on the Surgical Control of the Hyperlipidemias (POSCH): overall mortality, atherosclerotic coronary heart disease (ACHD) mortality, and ACHD mortality or myocardial infarction

The Program on the Surgical Control of the Hyperlipidemias (POSCH) was a secondary atherosclerosis intervention trial employing partial ileal bypass surgery as the intervention modality. For this report, we analyzed 105 subgroups in 35 variables in POSCH, chosen predominantly for their potential relationship to the risk of atherosclerotic coronary heart disease (ACHD). We defined potential differential effects as those with: (1) an absolute z-value > or = 2.0 for the subgroup, if the absolute z-value for the overall effect was < 2.0; and (2) an absolute z-value > or = 3.0 for the subgroup and a relative risk < or = 0.5, if the absolute z-value for the overall effect was > or = 2.0. For each of three major POSCH endpoints of overall mortality, ACHD mortality and ACHD mortality or confirmed nonfatal myocardial infarction, we found seven subgroups with a differential risk reduction in the surgery group as compared to the control group. Allowing for identical subgroups for more than one endpoint, there were 13 individual subgroups with differential effects. Of these, seven demonstrated internal consistency across endpoints, and five of these seven displaced external consistency with known ACHD risk factors and for biological plausibility: triglyceride concentration > or = 200 mg/dl; cigarette smoking; overt or borderline diabetes mellitus; a Minnesota ECG Q-QS code of 1-1; and obesity. A greater risk reduction, in comparison to the overall treatment effect, by the reduction of a single risk factor, hypercholesterolemia, in patients with at least two major ACHD risk factors was a provocative and an hypothesis-generating outcome of this analysis. The clinical implications of this finding may lead to more aggressive cholesterol intervention in patients with multiple ACHD risk factors.

Improvement in Obesity-associated Medical Conditions following Vertical Banded Gastroplasty and Gastrointestinal Bypass

Thirty-nine patients undergoing either Silastictrade mark ring vertical banded gastroplasty (SRVG, n = 23) or Roux-en-Y gastrointestinal bypass (RGB, n = 16) over a 1-year period were analyzed retrospectively. Weight loss averaged 40 kg (89 lb). Clinical diabetes mellitus was markedly improved in seven out of nine patients (p = 0.023). Shortness of breath resolved in all 26 patients who had this condition preoperatively (p < 0.001). Orthopedic problems, high blood pressure, and self-assessment of general health and quality of life were also dramatically improved. We conclude that bariatric surgery serves as an effective method to alleviate a multitude of conditions associated with morbid obesity.

A peritoneovenous shunt with an access port enables non surgical reversal of intraperitoneal catheter occlusion

Management of chronic peritoneal ascites by transfer of the fluid to the right atrium via peritoneovenous shunt (PVS) is often complicated by occlusion of the peritoneal catheter by one, or a combination, of the following: 1) omental plugging of drain holes, 2) fibrin obstruction of the lumen, and 3) encapsulation of the peritoneal segment by a cocoon. A PVS design that includes an access port facilitates the reversal of fibrin obstruction by urokinase. Eight dogs with implanted PVS were tested weekly for patency (indicated by the flow rate of saline into the peritoneum via the access port) and performance (indicated by the percent transfer of saline from the peritoneum to the vasculature). In 256 test sessions performed to date, 15 catheter occlusions occurred. Nine of these were reversed by one or two flushes with 5,000 units of urokinase via the access port. The remaining six were found to be occluded by cocoons (two), omentum (three), and fibrin (one). Although it is an effective treatment for ascites, the PVS is not in common use, because it has a relatively high occlusion rate. The access port and other features of the authors' PVS are designed to reduce the incidence of PVS occlusion.

Perception of quality of life before and after disclosure of trial results: a report from the Program on the Surgical Control of the Hyperlipidemias (POSCH)

The Program on the Surgical Control of the Hyperlipidemias (POSCH) was a randomized controlled clinical trial designed to ascertain whether cholesterol lowering induced by the partial ileal bypass operation would favorably affect overall mortality and the mortality and morbidity due to coronary heart disease. The trial results provided strong clinical and coronary arteriographic support for the beneficial effects of lipid modification for the reduction of atherosclerosis progression. At the same time, the surgery-assigned group experienced diarrhea and an increased incidence of kidney stones and gallstones compared to the control-assigned group. Identical quality of life determinations were performed in the POSCH study population shortly before disclosure of the trial results to the patients and shortly thereafter. The purpose of this dual assessment was to evaluate the effect of knowledge of outcomes on the patients' subjective evaluation of quality of life. The primary instrument utilized for analysis of the perception of quality of life in POSCH was the McMasters Health Index Questionnaire (MHIQ). In addition, four study-specific questions were asked of the trial patients. The results for the MHIQ before disclosure of trial results showed a difference (p = 0.07) favoring the control-assigned group (diet-treated), for the social function index of the MHIQ. After disclosure of the trial results, the difference was larger (p < 0.05). For the four study-specific questions, all differences favored the control-assigned group (p < 0.01) before and after disclosure of the trial results, with the exception of satisfaction with randomization allocation in the surgery-assigned group (p = 0.08). The intragroup MHIQ indices before and after disclosure of the trial results showed no suggestive significant differences, except in the surgery-assigned group, in which there was an improvement in the emotional function index after disclosure of the trial results (p = 0.03). The intragroup responses to the study-specific questions before and after disclosure of the trial results again showed no significant differences, except in the surgery-assigned group, in which there was an improvement in patient satisfaction with randomization allocation after disclosure of the trial results (p = 0.04).(ABSTRACT TRUNCATED AT 400 WORDS)