ILLUSTRATION: ASHISH Revisions in diagnostic biomarkers for medical conditions such as hypertension and diabetes have left patients befuddled. Mirror investigates.
Two months ago, when her weight touched 100 kg, Ritu Mirpuri decided to consult a dietician. The Mahalaxmi-based homemaker says she had no pre-existing health problems, but wanted to shed some weight all the same. Her bloodwork showed that Mirpuri’s glycated haemoglobin level (HbA1c) — the average blood sugar level over three preceding months — was 6.5 per cent. While the pathology lab’s report rated a reading of 6 to 7 per cent as within the ‘good control’ range, the diabetologist associated with the dietician prescribed a daily dose of 1,500 mg of metformin (typically used to reduce high blood sugar in patients with type 2 diabetes) for Mirpuri.
The 68-year-old, who felt uneasy about taking “diabetes medicine”, consulted her family doctor, who reassured her and told her that she was certainly not pre-diabetic. But, on her husband’s insistence, Mirpuri consulted another diabetologist, who not only informed her that she was pre-diabetic, but also prescribed an increase in the daily dosage of metformin.
Eventually, Mirpuri acted on the advice of the second diabetologist, but she often wonders whether she is really a diabetic. If she were to go by the guidelines issued by the American College of Physicians (ACP) last year, she would not need to take any diabetes medication. The influential ACP, whose guidelines are followed by doctors across the world, says that patients with type 2 diabetes should be treated to achieve an HbA1c of between 7 and 8 per cent, rather than 6.5 to 7 per cent. It claims that using drugs to target lower levels results in substantial harm rather than reduced fatalities, or a reduced risk of heart attack and stroke.
You could be hypertensive now
Glycaemic parameters are not the only markers to have been revised in the last five years. Revisions have been made across the world to obesity markers (the upper limit for morbid obesity, for example, was changed from a Body Mass Index of 35 to 32.5 for Indians five years ago by the Indian Council of Medical Research); LDL cholesterol (130 mg/dL was once the upper limit, but some doctors now target levels lower than 70), and hypertension (130/80 now). Though such revisions are par for the course in medicine, the ambiguity about diagnostic biomarkers and approaches in treatment has left several patients befuddled — and worried.
Chembur-based businessman Sumit Wig recently decided to go on anti-hypertensive drugs. But it took him over six months and visits to several GPs to arrive at that decision. “My GP told me that a reading of 130/90 was normal, but several others didn’t agree. They said anything above 120/80 had to be treated.”
Last year, Indian doctors adopted the guidelines of the American College of Cardiology and the American Heart Association, and lowered the hypertension marker from 140/90 (systolic blood pressure of 140 mm Hg and diastolic blood pressure of 90 mm Hg) to 130/80. The revision was based on the findings of the ‘SPRINT’ trial, which was conducted by America’s National Institutes of Health’s National Heart, Lung, and Blood Institute in 2017.
“A reading of 130/80 is now deemed ‘stage 1 hypertension’, and this must be addressed — particularly in patients with diabetes and heart disease,” says Dr Shashank Shah, one of the country’s foremost bariatricians. However, not all doctors agree with these findings. Dr Sundeep Mishra, a professor of cardiology at New Delhi’s All India Institute of Medical Sciences, for instance, says that guidelines should not be tweaked based on the results of a single trial. “And that too, a trial which was heavily criticised for the impractical way in which it tested BP readings – a method which is not replicable in most hypertension practices,” says Dr Mishra. “Part of the reason for lowering this BP limit could be the [pharma] industry’s push — they are likely to benefit hugely from this downward revision.” Dr Mishra says that if one were to go by the new definition, 60 per cent of adults in Delhi, or other Indian metros, for that matter, would now be labelled hypertensive.
Dr Shah, however, sees it differently. The lowering of the biomarker, he says, will alert people to the perils of the potentially life-threatening disease sooner, encouraging them to incorporate lifestyle changes to manage the condition. “It has been seen that the risk of vascular complications increases with higher BP values, so it’s worthwhile to start sooner to prevent these.”
Prevention is also the reason why the BMI marker for morbid obesity has been brought down by 2.5 points, says Dr Shaival Chandalia, an endocrinologist at Jaslok Hospital.
“In the West, a body mass index (BMI) of more than 30 to 35 is deemed obese, while in India, the range is 28 to 32.5,” says Dr Chandalia, explaining that Indians have been seen to develop diseases at a lower body weight. “We are known to be ‘thin fat’. Even at a lower body weight, our body fat percentage is much higher than that of Westerners, and it’s more concentrated in the abdomen. With obesity comes many diseases, and now it is also known to be a risk factor for many cancers. Naturally, it’s wiser to set a lower target and change your ways sooner.”
How bad is ‘bad cholesterol’?
The same argument is also used to justify the downward revision of low-density lipoprotein (LDL) or ‘bad’ cholesterol limit. Most Indian pathology labs define the ‘normal range’ for LDL-C as 85 to 130. However, in 2005, America’s National Cholesterol Education Program set the magic number at 100 mg/dL, and now some doctors have started targeting a level of under 70 mg/dL for their patients. “Once, the goal for LDL was 100 or below, but it was found that even at this level it posed a risk, so the guidelines were revised and the level brought down further,” says Dr Zakia Khan, an interventional cardiologist at Fortis Hospital, Kalyan.
A new — and popular — school of thought, however, suggests that there is no such thing as bad cholesterol. In an interview published in Expert Review of Clinical Pharmacology, David Diamond, the co-author of a widely acknowledged 2015 study on LDL cholesterol, said: “There have been decades of research designed to deceive the public and physicians into believing that LDL causes heart disease, when in fact, it doesn’t…Not only is there a lack of evidence of causal link between LDL and heart disease, the statistical approach statin advocates have used to demonstrate benefits has been deceptive…based on misleading statistics, exclusion of unsuccessful trials and ignoring numerous contradictory observations.”
Nihar Mehta, one of Mumbai’s top cardiologists, dismisses Diamond’s study. “LDL or bad cholesterol plays a direct role in building plaque and blocks arteries, which may cause everything from heart attacks and strokes to kidney damage.” Dr Mehta is a member of two committees that compute biomarkers specific to India — Lipid Consensus Statement (a committee formed by the Academy of Cardiology), and the Indian Hypertension Guidelines Committee. He says that guidelines are never carved in stone. “There can be no blanket rule in medicine,” Dr Mehta says. “If a person has had a stent implanted, or has suffered a stroke, for example, then you’d target a level lower than 70. In some subset of patients, a specialist may even target an LDL of 55. It really depends on the risks for that patient, and differs from case to case.”
Dr Zakia Khan says the same is true of BP. “While a single reading of 140/90 need not raise alarm bells [for a person with no other health conditions], if it remains at this level for, say, three days — a monitor may be attached to the patient to understand his or her BP pattern, even recording it when he or she is asleep — it could indicate stage 1 hypertension, and that must be tackled.”
The new normal
Addressing the confusion over the relaxed HbA1c guidelines, Dr Pradeep Gadge, diabetologist and endocrinologist, Gadge Diabetes Centre, says, “The relaxed guideline of 7 to 8 per cent was issued by the American association of family physicians, not the American Diabetes Association (ADA). The reasoning behind this is that regular monitoring of patients poses a challenge for family physicians vis-à-vis specialists, who monitor their patients’ glucose values, and assess how therapy is working more closely. The less stringent targets were set to ensure that patients who were not being monitored closely didn’t end up with hypoglycaemia (low blood glucose).”
Dr Chandalia adds that targets have to be decided based on the patient’s pre-existing health conditions, age, life-expectancy, and other factors. Although this sounds like a common-sense approach, in practice, as 33-year-old Amrita Korwar and her mother Ranjana found, it doesn’t always work. “A year ago my mother was diagnosed with diabetes, and the doctor promptly started her on medication. But, in no time, she became hypoglycaemic,” says Amrita, a Bandra resident and brand manager.
She says that even when the doctor reduced the […]
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