Campaigner in hit and miss with facts about Nigeria’s stroke burden

13th January 2020 By: Africa Check

Campaigner in hit and miss with facts about Nigeria’s stroke burden

On World Stroke Day in 2019, Nigerian media reported on the toll of the life-threatening condition, which is caused by the sudden interruption of blood supply to the brain.

Many quoted the Nigerian Stroke Organisation. Its president, Prof Abayomi Ogun, made a number of claims about the cost of stroke in Africa’s most populous country. 

We checked three of his claims reported in the Daily Trust, a national newspaper.

Claim: In Nigeria, stroke is the most common medical emergency in most hospitals.

Verdict: unproven

Ogun told Africa Check he had been accurately quoted, and shared six academic and medical research papers to support his claim. 

These were: 

We asked several experts if this evidence supported the claim.

Comprehensive survey needed

Dr Abiodun Bello, a consultant neurologist at the University of Ilorin Teaching Hospital, reviewed the papers shared with us. More evidence was needed, he said.

“One would need to look for articles on medical admissions as a whole out of which the percentage that form stroke patients can be determined.” 

Bello said stroke was a common medical emergency, but if primary, secondary and tertiary health centres were all considered, it was unlikely to be the most common. 

Consultant neurosurgeon Prof Timothy Odebode agreed that a comprehensive survey would be required. 

“In my field, I believe the most common medical emergency is head injury. For a neurologist, it is stroke. Each medical field has its most common medical emergency,” Odebode said.

Dr Oluchi Ekenze, a consultant neurologist at the University of Nigeria Teaching Hospital, agreed. 

“Medical emergency is a broad topic. If the claim was that stroke is the most common neurological emergency then I would say it is true,” she said.

“For adult internal medicine, which is a subspecialty in medical emergency, the claim you are fact-checking is true. However, there are other subspecialties in medical emergency.”

Prof Tanimola Akande, a consultant public health physician, told Africa Check that other emergencies were more common. These included cardiac failure, severe hypertension, gastroenteritis and bronchial asthma. 

Most common neurological emergency

But Akande added that the claim could be true for specific age groups and hospital settings.

Emmanuel Sanya, a consultant physician and neurologist, told Africa Check that many studies showed stroke was the leading cause of medical admission in adults and elderly patients in Nigeria. 

“It is equally the most common neurological diagnosis warranting admissions,” Sanya said.

Dr Muhammed Adeboye, a consultant paediatrician, said stroke was the most common medical emergency “among adults”. But “in children, I would say febrile convulsion” or seizure was most common.

Based on this, we rate this claim as unproven.

Claim: Stroke accounts for up to eight out of 10 neurological hospital admissions.

Verdict: misleading

The Nigerian Stroke Society’s Ogun directed us to a study on admissions for neurological diseases in Kano, which he said was Nigeria’s most populous state.

Out of 6 282 admissions at the Aminu Kano Teaching Hospital from January 2005 to September 2008, some 980 were for neurological diseases. The study found stroke accounted for 77.6% of these.

Dr Uduak Umana, secretary of the Neuroscience Society of Nigeria, said the figure would likely change from one healthcare facility to another.

“I wouldn’t state for a fact that stroke accounts for up to eight out of 10 neurological admissions. It varies.” 

Yakub Nyandaiti, a professor of neurology at the college of medical sciences, University of Maiduguri, said it would be inaccurate to draw a general conclusion that stroke accounts for eight out of 10 neurological admissions based on findings from one hospital.

“Findings or the data from the hospital (mentioned in the claim) is not a general picture of what is going on in all hospitals in Nigeria. Also, a claim must have a time frame. That is, the claim should read in the last five to 10 years, or something,” he said.

As admissions at one hospital are not representative of ‘most hospitals’ in Nigeria, we rate this claim as misleading.

Claim: At least 100 000 stroke cases occur every year [in Nigeria].

Verdict: correct

Other organisations have given different figures. In October 2019, the chief executive officer of Stroke Action Nigeria, Rita Melifonwu, was widely reported as saying that “in Nigeria, stroke continues to affect 200 000 people annually”. We have asked her for the source of this statistic.

A 2017 article in the Lancet journal also made an estimate of 200 000 new cases, adding that Nigeria did not yet have a national stroke registry.

Ogun told Africa Check that his number was likely “underestimated”, which was why he said “at least”. He gave as evidence a 2007 study in the Surulere Local Government Area of Lagos state. This focused on 189 first-ever cases of stroke, which were then adjusted for age to allow for comparisons, to find an incidence rate of 54.08 cases per 100 000 people a year.

This study was “the most up to date reference we have on the incidence of stroke in Nigeria”, he said.

Ogun said that with “Nigeria’s 2019 population being estimated at over 200-million, the number of incidents (new) stroke cases will be at least 108 000 per year”.  

But Nigeria’s population is disputed, with a census last conducted in 2006.

Dr Abiodun Bello, a consultant neurologist at the University of Ilorin Teaching Hospital, told Africa Check the evidence was “sufficient since it is an estimate derived from incidence reported”.

Bello asked us to check further with the World Health Organization or the global burden of diseases study led by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington in the US.

WHO communications officer Paul Garwood told Africa Check the organisation did not have specific data on the number of new cases of stroke in Nigeria in a year. It only had data on how many deaths were due to cerebrovascular disease, he said. But this didn’t cover Nigeria.

But Dr Valery Fiegin, who heads the neurology section at the global burden of diseases study, told Africa Check that their latest 2019 estimates showed that there were “over 149 000” new strokes in Nigeria. This could have been as high as 167 000 or as low as 133 000. 

We therefore rate Ogun’s claim of ‘at least 100 000’ as correct.

Researched by Motunrayo Joel, Africa Check, a non-partisan fact-checking organisation. View the original piece on their website.