Staggering cost of obesity

For a single individual, the burden of obesity can be enormous; for a society, the projected costs for health and economics are hard to fathom (Lancet 2011; 378: 815-25).

By 2030, this report projects that there will be 65 million more obese adults in the US and 11 million more in the UK.  This is expected to cause an additional  6-8.5 million cases of diabetes, 5.7-7.3 million cases of heart disease/stroke, about 500,000 cases of cancer, and loss of 26-55 milion life years.  The medical costs are estimated to increase $48-66 billion/year in the US.

These projections are based on expected increases in the percentage of individuals who are obese.  In 2008, approximately 32% of US adult men were obese based on BMI; in 2030, the projected number is 50-51% for men.  Among US women: 35% in 2008 –> 45-52% in 2030.

To flatten the curve on spending, we will need to look at flattening other curves.

Additional references:

  • A liver disease tsunami
  • -NEJM 2011; 365: 1597. Persistence of hormonal adaptations with weight loss. Due to persistent changes in hormones like leptin & peptide YY, hard to keep wt off -result is increased appetite.
  • -NEJM 2009; 360: 859. Composition of diet does not seem to be important. Total calories important.
  • -Pediatrics 2007; 120: suppl 4: S164-S287.
  • -NEJM 2007; 357: 370. obestiy spreads in social network.  Your friends may be more influential than your genetics.
  • -Gastroenterology 2007; 132: 2085-2276. Special issue on obesity issues.
  • -NEJM 2006; 355: 1593. Case review on obesity c DDx and mgt.
  • -Pediatrics 2003; 112: 424. Position paper on prevention in childhood.
  • -Gastroenterology 2001; 120: 669-681. (review)
  • -J Pediatr 2005; 147: 429. TV viewing predicts adult BMI.
  • -Lancet 2001; 357: 505-8. One extra soda/day incr risk of obesity by 60%
  • -NEJM 1999; 341: 1097. BMI & mortality.

Common to be “D-ficient”

Many of the children that a pediatric gastroenterologist sees are at risk for Vitamin D deficiency, including children with inflammatory bowel disease, cystic fibrosis, celiac disease, and liver diseases.  In addition, vitamin D deficiency is widespread: in U.S. 50% of children aged 1-5 years and 70% 6-11 years are vitamin D deficient or insufficient. A thorough review on this “D-lightful” vitamin was in a recent JPEN (JPEN J Parenter Enteral Nutr 2012; 9S-19S).

History: In 1822 Sniadecki recognized children in urban but not rural Poland developed rickets. He postulated the effects of the sun as the reason for rickets; his idea was dismissed.  In 1920s, the concept of irradiating milk to prevent rickets emerged. In 1950s, outbreak of hypercalcemia in infants in Great Britain was thought to be related to vitamin D fortification and curtailed this practice in Europe.  However, these cases were likely due to Williams syndrome.

Sources of vitamin D: oily fish (salmon), cod liver oil, some mushrooms, egg yolk, & sunlight. Exposure of an adult in a bathing suit to one minimal erythemal dose (MED) is equivalent to ingesting 20,000 IUs of Vitamin D. (The minimal dose that induces any visible reddening at that point is defined as one MED.)

Effect of sunscreen: A sun protection factor (SPF) of 30 absorbs approximately 98% of solar ultaviolet radiation & thus lowers vitamin D production by 98%.

Ethnicity: Melanin is an effective SPF.  A person of african-american descent, on average, has an SPF of 15, which reduces vitamin D production by 90%.

Age: Aging decreases 7-dehydrocholesterol in human skin.  Due to this, the elderly produce much less vitamin D.  For example, a 70 year old has a 75% reduction compared to a 20 year old.

Forms of vitamin D:  25-hydroxyvitamin D (25OH-D) is the major circulating form of vitamin D & physicians measure 25OH-D. 25OH-D is metabolized in kidney to 1,25-dihydroxyvitamin D (1,25OH-D), also called calcitriol.  This is the most biologically-active and is responsible for increasing intestinal calcium absorption and mobilizing calcium from bone.  However, 1,25OH-D provides no information vitamin D deficiency; it can be elevated or normal in deficiency states.

  • Cholecalciferol (vitamin D-3) is formed in the skin from 5-dihydrotachysterol.
  • Ergocalciferol (Vitamin D-2) is the form in Drisdol (8000 IU/mL) & Ergocalciferol Capsules (1.25 mg =50,000 USP Units)

Vitamin D deficiency:  The exact numbers are debated.  The institute of medicine (IOM) has considered individuals deficient if 25OH-D is <20 ng/mL.  The Endocrine Society and the author suggest vitamin D deficiency as <20 ng/mL & insufficiency as <30 ng/mL.  The author recommends ideal levels between 40-60 ng/mL.

Consequences of deficiency:

Osteoporosis, Osteopenia, Rickets (see references below): Bone weakening occurs due to loss of phosphorus from the kidneys.  Vitamin D deficiency lowers accrual of calcium in skeleton and leads to osteoporosis, osteopenia, and rickets. Imaging for rickets: the best single radiographic view for infants and children younger than 3 years is an anterior view of the knee that reveals the metaphyseal end and epiphysis of the femur and tibia. This site is best because growth is most rapid in this location, thus the changes are accentuated.

Nonskeletal consequences: vitamin D deficiency is associated with increased risk for preeclampsia, URIs, asthma, diabetes (type 1), multiple sclerosis, hypertension, and schizophrenia.

Treatment:

  • Infants who are breastfed should be receiving supplemental vitamin D, 400 IU/day.
  • Adults/children (>1 year) RDA 600 IU/day –mostly from diet per IOM. Yet author states, “it is unrealistic to believe that diet alone can ….provide this requirement.”
  • In vitamin D deficient patients: (initial treatment) 2000 IU/day or 50,000 IU/week for 6 weeks.
Toxicity from vitamin D (from NEJM 2010; 364: 248-254.): “Toxicity from vitamin D supplementation is rare and consists principally of acute hypercalcemia, which usually results from doses that exceed 10,000 IU per day; associated serum levels of 25-hydroxyvitamin D are well above 150 ng per milliliter (375 nmol per liter). The tolerable upper level of daily vitamin D intake recently set by the Institute of Medicine (IOM) is 4000 IU.”

Additional references:

  • -Pediatrics 2008; 122: 398. Should give 400 IU/day to breastfed babies. Consequences of Vit D deficiency: increased risk for DM, multiple sclerosis, cancer (breast, prostate,colon), rickets, and schizophrenia. Article lists vit D content of foods (high in cod liver oil, shrimp, fortified milk, many fish). Severe deficiency when < 5ng/mL, deficient if < 15 ng/mL; probably should be >32 ng/mL. Causes of vit D deficiency: decreased synthesis (due to lack of sun -skin pigmentation, sunscreen/clothing, geography, clouds), decreased intake, decreased maternal stores & breastfeeding, malabsorption (eg celiac, CF, EHBA, cholestasis), increased degradation; treatment of rickets: double-dose of vitamin d (~1000 IU/day for babies & 5000 for older kids) x 3-4 months along with calcium (30-75/mg/kg/day). Follow Ca/phos/alk phos monthly. Alternatively, give ~100,000 units over 1-5 days.
  • -JPEN J Parenter Enteral Nutr. 2011;35:308-316-Results: The study included 504 IBD patients (403 Crohn’s disease [CD] and 101 ulcerative colitis [UC]) who had a mean disease duration of 15.5 years in CD patients and 10.9 years in UC patients; 49.8% were vitamin D deficient, with 10.9% having severe deficiency. Vitamin D deficiency was associated with lower HRQOL (regression coefficient –2.21, 95% confidence interval [CI], –4.10 to –0.33) in CD but not UC (regression coefficient 0.41, 95% CI, –2.91 to 3.73). Vitamin D deficiency was also associated with increased disease activity in CD (regression coefficient 1.07, 95% CI, 0.43 to 1.71). Conclusions: Vitamin D deficiency is common in IBD and is independently associated with lower HRQOL and greater disease activity in CD. There is a need for prospective studies to assess this correlation and examine the impact of vitamin D supplementation on disease course.
  • -JPGN 2011;53: 361. similar prevalence of low Vitamin D as general population –58% with less than 32.
  • -JPGN 2011; 53: 11. Guidelines for bone disease with inflammatory bowel disease.
  • -Pediatrics 2010; 125: 633. Increasing Vit D deficiency noted in minority children. n=290. 22% w levels <20, 74% <30.
  • -Hepatology 2011; 53: 1118. Good vitamin D levels are another favorable predictive factor in antiviral response to Hep C along with IL28B.
  • -NEJM 2010; 364: 248-254. Vitamin D insufficiency. Levels between 20-30 may be OK -not enough evidence to determine conclusively whether this level is detrimental
  • -J Pediatr 2010; 156: 948. High rate among african americans with asthma, 86%. n=63.
  • -Pediatrics 2009; 124:e362. n=6275. 9% of pediatric patients vit D deficient & 61% were insufficient.
  • -Pediatrics 2009; 124:e371. n=3577. low 25OH-D levels inversely assoc with SBP/metabolic syndrome.
  • -NEJM 2009; 360: 398. case report of rickets
  • -J Pediatr 2003; 143: 422 & 434
  • -Pediatrics 2003; 111: 908. 200 IU Vit D recommended for all breastfed infants.
  • -J Pediatr 2000;137: 153 & 143.. Nutritional rickets–primarily in blacks; rec vitamin D 400 IU per day.

Sarcopenia, fatigue, and nutrition in chronic liver disease

Several articles from a recent Clinical Gastroenterology and Hepatology have addressed nutritional aspects of chronic liver disease.

1. Sarcopenia?  This term refers to generalized loss of skeletal muscle.  It does not equate to malnutrition though there is significant overlap.  (Clinical Gastroenterology and Hepatology 2012; 10: 166-73 & editorial 100).  In this study, 112 adults with cirrhosis had CT scans which examined skeletal muscle at the L3 level; 40% had sarcopenia. Sarcopenia was independently associated with mortality and was not reflected in MELD score.  Patients had increased risk of death from sepsis and liver failure (HR 2.18).  Thus, sarcopenia joins hyponatremia, refractory ascites, hepatic encephalopathy as additional factors which add prognostic information to MELD score.

2. Fatigue in cirrhosis. (Clinical Gastroenterology and Hepatology 2012; 10: 174-81 & editorial 103).  Fatigue is common in cirrhosis and is multifactorial.  In this prospective study, 108 patients were evaluated with a fatigue impact scale. Fatigue improved after liver transplantation. Fatigue can be peripheral due to muscle weakness and dysfunction. And, fatigue can be central due to difficulty performing physical and mental activities.  Central fatigue is associated with an increased perceived effort for tasks and often related to depression; this type of fatigue is much more common with cirrhosis.  Although improved, fatigue often does not completely resolve with liver transplantation.

3. Nutrition recommendations. (Clinical Gastroenterology and Hepatology 2012; 10: 117-25).  A summary of nutrition recommendations in adults  with chronic liver disease is given in this article.  One common misconception is protein restriction.  This is not beneficial.  Protein recommendations are for adult patients with cirrhosis to receive 1-1.5 g/kg/day.  This amount is higher than for healthy individuals.  Protein restriction leads to protein catabolism, muscle breakdown and increases the likelihood of hepatic encephalopathy.

Additional references:

  • -Age Ageing 2010; 39: 412-23.  Sarcopenia consensus definitions in older people.
  • -Gastroenterology 2008; 134: 1741. Evaluation and management of end-stage liver disease in children. Recs vaccines due to functional asplenia/portal hypertension at age 2 for Neisseria (MCV4) or polysaccharide (MPSV4); at 6 weeks of age for pneumococcal conjugate vaccines. Reviews nutrition, varices, ascites, encephalopathy….
  • -Liver Transplant 2008; 14: 585-591. Poor growth often due to growth hormone resistance. Chronic malnutrition is a factor, but children with advanced liver dz may not grow despite adequate calories. Recs: for chronic liver dz: 130-150% of RDA based on ideal body wt; in infants 120-150 cal/kg/day. Increase MCT either thru formula or supplemental MCT.
  • -Liver Transplant 2006; 12: 1310. Review article on nutrition for OLTx patient.
  • -JPGN 2000; 30: 361. nutrition review and chronic liver disease.

What to make of FODMAPs

Consumption of FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) may trigger irritable bowel syndrome (IBS) symptoms.  Some research indicates that a diet low on FODMAPs may be beneficial (J Hum Nutr Diet 2011; 24: 487-95).  This study tried to assess whether a low FODMAPs diet which had been reported from a single center in Australia would be effective for IBS.

In this study, consecutive patients with IBS were divided into two groups.  39 received standard dietary advice based on UK National Institute for Health and Clinical Excellence (NICE) guidelines.  43 patients were placed on a low FODMAP dietary advice.  Patients were selected into each group consecutively (not randomized). This study reported a 76% satisfactory symptom response in the FODMAP group vs a 54% response in the control group (p=0.038).  Overall, 86% of FODMAP group had improved composite score compared with 49% of standard treatment group. Specific improvements were noted in bloating, abdominal pain, and flatulence.  The average age of the study population was 38 and 71% were females.  60% had diarrhea-predominant IBS.

NICE guidelines for IBS:

  • Healthy eating principles: regular eating, taking time to eat
  • Limit high fat foods and fizzy drinks
  • Limit insoluble fiber for diarrhea and gradually increase for constipation
  • Limit sugar-free sweets and foods with sorbitol
  • Limit fruit to 3 portions/day
  • Avoiding ‘resistant’ starch may be useful (eg. sweetcorn, green bananas, part-baked and reheated bread)
  • Addition of oats and linseeds may be helpful

Low FODMAP diet

  • Reduce high fructan foods (eg wheat and onion)
  • Reduction in high galactooligosaccharide foods (eg chickpeas, lentils)
  • Reduce high polyol foods and polyol-sweetened sources.  Replace with suitable fruits and vegetables
  • In patients with lactose malabsorption, reduce high lactose foods (eg milk, yoghurt) to smaller volumes or substitute lactose-free products
  • In those with fructose malabsorption, decrease excess fructose

Of course, reading the author’s description of a low FODMAP diet is confusing.  Translation:

Include more bananas, blueberries, lettuce, potatoes, gluten-free breads or cereals, rice, oats, hard cheeses, lactose-free milk, sugar, molasses, and artificial sweeteners that do not end in “ol.”

Avoid/eliminate apples, pears, canned fruits in natural juices, high-fructose corn syrup, cows’ milk (due to lactose), soft cheese, broccoli, cabbage, pasta, bread, baked goods from wheat/rye, mushrooms, and sweeteners like sorbitol or others that end in “ol.”

Since this diet has attracted more widespread attention, basic familiarity is important for all physicians who treat IBS.  A useful resource to explain this diet is the Wall Street Journal:

http://online.wsj.com/article/SB10001424052970204554204577023880581820726.html

This link has a good table illustrating the recommended dietary choices.

Whether FODMAPs will be superior to other dietary advice for IBS is still uncertain.  Though, given the limited number of effective treatments for IBS, this small study is a promising development.

Additional references:

  • -Clin Gastro & Hep 2009; 7: 706. n=17. 13 responded to very low carb diet (<20g/day)
  • -Clin Gastro & Hep 2008; 6: 765. Dietary triggers for IBS include fructose/fructans: honey, high fructose corn syrup, wheat, fruits.
  • -IBD 2006; 13: 91. Dietary guidelines for IBS.
  • -Clin Gastro Hepatol 2005; 10: 992-996. Obesity increases IBS symptoms; diet with low fat, high fruit/fiber have fewer symptoms
  • -Gut 2004; 53: 1459-1464. Food elimination based on IgG antibodies. Patients did better on diet with implicated foods than with control diet (diet was blinded/randomized).
  • -Am J Gastro 2011; 106: 508-514. randomized, double-blind trial showing efficacy of GFD for non-celiacs.  60% vs 32& placebo response.
  • -Nutr Clin Pract. 2011;26:294-299.  GFD for non-celiacs.
  • -Gastroenterology 2011; 141: 1941./Am J Gastro 2011; 106: 915.  Exercise improves IBS symptoms.

Holes in the fiber theory

Since the 1970s, it has been accepted that diverticular disease is related to low fiber intake and the Western diet.  Problem is that this might not be right (Gastroenterology 2012; 142: 205-10).  In this observational cross-sectional study (n=2104), low dietary fiber was not associated with diverticulosis; just the opposite.  High fiber intake, after adjusting for other factors, had an adjusted prevalence ratio of 1.3.  Due to the nature of the study, there may be potential bias that would not be present with a prospective study, especially with regard to dietary recall.  An editorial in the same issue (pg 205-07) lists three other studies; two of these also could not demonstrate a protective effect of fiber.  In addition to these findings, this study did not find an association between fat, red meat, physical activity and diverticulosis.

Although these data throw a big question mark regarding the pathogenesis of diverticular disease, this does not mean you should throw away your fiber bars quite yet.  Although low fiber may not cause diverticular disease, several large prospective studies have been completed which convincing show an association with lower complications/hospitalizations among individuals with higher fiber intake.  In addition, increased fiber in the diet has been shown to lower cardiovascular complications.

Additional references:

  • -Br Med J 1971; 2: 450-54.  Seminal article on diverticular disease and association with Western countries with low fiber intake.
  • -Am J Clin Nutr 1994; 60: 757-64.  Prospective study showing benefits of fiber in preventing diverticular complications (n=47,888); RR=0.58 for developing symptomatic diverticulitis.
  • -BMJ 2011; 343: d4131.  EPIC study, n=47,033, showing benefit of fiber in reducing hospitalizations due to diverticular dz over 12yrs (0.59 RR)
  • -NEJM 1999; 340: 169. fiber does not decrease Colon Ca risk.
  • -NEJM 2000; 342: 1149 & 1159. fiber does not decrease risk of recurrent adenomas.
  • -Am J Clin Nutr 2000; 70: 1433-1438. Fiber lowers cholesterol & can decrease risk of heart attack by 15%.

More evidence that breastfeeding improves cognitive development

A large cohort study from the United Kingdom with 11,101 term infants and 778 preterm infants shows improved cognitive development when infants are breastfed.  J Pediatr 2012; 160: 25-32.  There have been a number of previous studies as well that have shown that breastfed children have an IQ that is ~5 points higher than nonbreastfed children; however, when adjustment for confounders, especially maternal education, this effect is weaker.  Since this is an observation study (randomized blinded study would be impossible), it is difficult to control for all variables.  Nevertheless, prolonged breastfeeding, more than 2 months in preterm and more than 4 months in term infants, is associated with higher cognitive development.

Additional references:

  • Am J Clin Nutr 199; 70: 525-35.
  • BMJ 2006;  333: 945.
  • Arch Gen Psychiatry 2008; 65: 578-84.
  • Paediatr Perinat Epidemiol 2003; 17: 81-90.

Other refences:

  • J Pediatr 2009; 155: 421.  Breastfeeding may have possible protective effect from developing inflammatory bowel disease.  Review of multiple studies.
  • J Pediatr 2002; 141: 764.  Breastfeeding may protect against obesity.
  • BMJ 2007; 335: 815-20.  Longer time of breastfeeding does not reduce allergy/asthma. n=17,046 pairs of mother-infant (13,889 followed up at age 6.5yrs)