Gaps in the Evidence Base

There are bot h healt h and economi c cons equences of ob es it y. Obesit y is associ at ed with increas ed ris k of t ype 2 di abet es, coronar y heart di seas e, stroke, congestive heart fail ure, h ypert ens ion, d ys lipidaemi a, gall bladder diseas e, os teoarthriti s and sleep apnoea 1 , 4 , 5. Others are infert ilit y,

pol yc ys t ic ov ari es, pregnanc y compli cati ons such as neural tube defects, perinat al m ort alit y, pre -ecl ampsi a, gest at ional di abet es , pre -t erm l abour and deep vein t hrombosis , st ress i nconti nence, ps ychological depression and soci al disabi lit y and low i ncom e. Also certain cancers have been associ ated

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with obesit y li ke those of breast , ovari an, endom et ri al, gal l bl adder and col oni c cancers 1 , 4 , 5 , 1 8.

The health problems associ at ed wi t h obesit y in chil dren and adoles cence incl ude heat intol erance, breat hlessness on ex ert ion, ti redness and fl at feet ⁴.

The economi c consequences of obes it y has been es tim ated at about 3 -9%, i n cost s, of tot al health care expendit ure in t he Uni ted States of Am eri ca.

In Australi a, it is 2% whil e in Europe it is between 1% and 5% 4 , 5 , 6. Also, it has been shown that Bod y M as s Index is as sociated wit h increas ed annual rat es of inpati ent da ys , num ber and cost s of out pati ent pharm ac y and laborator y s ervices . The m ain bulk of the economi c costs of obesit y ari se from t reati ng obesi t y rel at ed disorders like h ypert ens ion, coronar y heart diseas e and t ype 2 di abet es. Thus, the economi c burden of obesit y is li kel y t o get wors e, even i f t he preval ence of obesi t y rem ains t he s ame 4 , 5 , 6.

There are als o i ndi rect costs of obesit y. Thes e are in terms of l ost output i n the econom y as a result of si ckness, abs ent eeism, prem ature death, pa ym ent of s ickness and unem plo ym ent benefits, loss of producti vit y and j ob discrimi nation. M oreover, it has been found t hat obese persons att ain lower levels of occupati onal prest i ge and lower incom e t han non -obes e persons4 , 5 , 1 8.

While s urger y has been us ed to manage obesit y, obesit y it s elf is also known to compli cat e surgeri es. Known surgi cal compli cati ons of obesit y incl ude wound dehi scence, throm boembolism, wound infection and poor wound heali ng due t o poor vascul arisation ^{1 , 1 9}.

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In additi on, contraception in the poorl y mot ivated obes e patients constitut es a challenge as commonl y avai labl e hormonal met hods m a y not be advisabl e^{2 0}.

Obesit y has als o been strongl y ass ociat ed with increas ed preval ence of left ventri cular h ypertroph y ( LVH). A dose -res pons e rel ations hip bet ween t he severit y and durat ion of obesit y and preval ence of l eft vent ri cul ar h ypert roph y has been obs erved. The ris k of LVH for ever y 2 kg/m² increas e in bod y m ass i ndex has been estim ated at 47% i ncrease i n men and 51%

increase in wom en^{2 1}.

Obesit y is a nutritional disorder whi ch resul ts from a positi ve energy bal ance. However, a negati ve energy bal ance will l ead to nutritional depleti on or undernutrition with cons equential wei ght l oss 1 , 2 , 4 , 6.

Undernut riti on can occur in bot h adult s and chil dren under cert ain conditions. These are i nadequat e diet ar y int ake, increas ed m et aboli c dem and b y the bod y and increased l oss of nut ri ents from the bod y ².

1.7.1 Inad equate di e tary in tak e: Thi s ma y be due t o ins uffici ent amount of avail abl e food because of drought, pest s (such as locust ), famine or war or insuffi ci ent int ake of good qualit y food especiall y i nadequate i nt ake of prot ei n. This m a y be as a result of povert y, i gnoran ce and local beli efs about food ².

1.7.2 In creas ed Metabol ic demand b y th e body : Thi s occurs i n chil dren duri ng growth and development, and in women during pregnanc y and lactation. Underl yi ng ill nesses al so cause increas ed m et abolic dem and of food b y t he b od y e.g. infecti ons, traum a, fever, th yrot oxicosis and di abet es mellit us ².

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1.7.3 Increas ed los s of nutrien ts from the body : Thi s can occur i n dis eases like nephroti c s yndrome and ot her renal disorders, and in m al -absorptive and mal -di gest ive st ates like protei n-l osi ng enteropat h y (loss of prot ei n into t he lumen of the int esti nes in such a m agnitude as to caus e h ypoprot einaemi a as in s evere hookworm infest ation) and enteric fistul as².

The overall effect of undernut rition is to reduce (or lower) Bod y M ass Index ¹.