New paper out: “Indoor apparent temperature, cognition, and daytime sleepiness among low-income adults in a temperate climate”
New paper out! I’m really proud to have been a part of this research, now published in Indoor Air (Wiley)
We put temperature monitors in 34 low income Detroit homes and tested to see if high temperatures had anything to do with daytime sleepiness or word recall.
“The burden of temperature-associated mortality and hospital visits is significant, but temperature’s effects on non-emergency health outcomes is less clear. This burden is potentially greater in low-income households unable to afford efficient heating and cooling. We examined short-term associations between indoor temperatures and cognitive function and daytime sleepiness in low-income residents of Detroit, Michigan. Apparent temperature (AT, based on temperature and humidity) was recorded hourly in 34 participant homes between July 2019-March 2020. Between July-October 2019, 18 participants were administered word list immediate (WLL) and delayed (WLD) recall tests (10-point scales) and the Epworth Sleepiness Scale (24-point scale) 2–4 times. We applied longitudinal models with nonlinear distributed lags of temperature up to 7 days prior to testing. Indoor temperatures ranged 8–34°C overall and 15–34°C on survey days. We observed a 0.4 (95% CI: 0.0, 0.7) point increase in WLL and 0.4 (95% CI: 0.0, 0.9) point increase in WLD scores per 2°C increase in AT. Results suggested decreasing sleepiness scores with decreasing nighttime AT below 22°C. Low-income Detroit residents experience uncomfortably high and low indoor temperatures. Indoor temperature may influence cognitive function and sleepiness, although we did not observe deleterious effects of higher temperatures.”
New publication: An urban-to-rural continuum of malaria risk: new analytic approaches characterize patterns in Malawi
12 years in the making! Our new paper from partners at the University of Michigan and the #Malawi College of Medicine on new approaches to defining urban and rural environments in the context of malaria risk is now out in #Malaria Journal.
It was the last chapter in my dissertation to be published (all the rest were published when I was still in grad school.)Short version: malaria is complicated and really local. Malaria transmits poorly in urban and environments and well in rural environments. There’s urban like spaces in “rural” areas and rural-like spaces in “urban” areas, demanding a more nuanced view of what those terms really mean.
We know that malaria is a “rural” problem, but not all “rural” spaces are the same. Even in the country, there are “urban like” spaces and in “rural like” spaces even in the largest cities in Sub-Saharan Africa. Could those spaces impact malaria risk? If so, shouldn’t we redefine what we mean by urban vs. rural to inform intervention strategies to better target resources?
Here, we combine GIS and statistical methods with a house to house malaria survey in Malawi to create and test a new composite index of urbanicity and apply that to create a more nuanced risk map.
The urban–rural designation has been an important risk factor in infectious disease epidemiology. Many studies rely on a politically determined dichotomization of rural versus urban spaces, which fails to capture the complex mosaic of infrastructural, social and environmental factors driving risk. Such evaluation is especially important for Plasmodium transmission and malaria disease. To improve targeting of anti-malarial interventions, a continuous composite measure of urbanicity using spatially-referenced data was developed to evaluate household-level malaria risk from a house-to-house survey of children in Malawi.
Children from 7564 households from 8 districts in Malawi were tested for presence of Plasmodium parasites through finger-prick blood sampling and slide microscopy. A survey questionnaire was administered and latitude and longitude coordinates were recorded for each household. Distances from households to features associated with high and low levels of development (health facilities, roads, rivers, lakes) and population density were used to produce a principal component analysis (PCA)-based composite measure for all centroid locations of a fine geo-spatial grid covering Malawi. Regression methods were used to test associations of the urbanicity measure against Plasmodium infection status and to predict parasitaemia risk for all locations in Malawi.
Infection probability declined with increasing urbanicity. The new urbanicity metric was more predictive than either a governmentally defined rural/urban dichotomous variable or a population density variable. One reason for this was that 23% of cells within politically defined rural areas exhibited lower risk, more like those normally associated with “urban” locations.
Its always a thing to celebrate, getting these new papers out. This one covers a topic close to home. After years of doing global health work, I never thought I’d be doing domestic health and even less certain that I’d be covering topics just down the road from me.
Together with partners from Wayne State University (Health Urban Waters), UM-Dearborn and the University of Michigan Ann Arbor, we characterized the state of recurrent flooding in Detroit, MI and explore possible public health impacts. The article appears in the International Journal of Environmental Research in Public Health. This was extremely rewarding work.
Article is open access.
Household flooding has wide ranging social, economic and public health impacts particularly for people in resource poor communities. The determinants and public health outcomes of recurrent home flooding in urban contexts, however, are not well understood. A household survey was used to assess neighborhood and household level determinants of recurrent home flooding in Detroit, MI. Survey activities were conducted from 2012 to 2020. Researchers collected information on past flooding, housing conditions and public health outcomes. Using the locations of homes, a “hot spot” analysis of flooding was performed to find areas of high and low risk. Survey data were linked to environmental and neighborhood data and associations were tested using regression methods. 4803 households participated in the survey. Flooding information was available for 3842 homes. Among these, 2085 (54.26%) reported experiencing pluvial flooding. Rental occupied units were more likely to report flooding than owner occupied homes (Odd ratio (OR) 1.72 [95% Confidence interval (CI) 1.49, 1.98]). Housing conditions such as poor roof quality and cracks in basement walls influenced home flooding risk. Homes located in census tracts with increased percentages of owner occupied units (vs. rentals) had a lower odds of flooding (OR 0.92 [95% (CI) 0.86, 0.98]). Household factors were found the be more predictive of flooding than neighborhood factors in both univariate and multivariate analyses. Flooding and housing conditions associated with home flooding were associated with asthma cases. Recurrent home flooding is far more prevalent than previously thought. Programs that support recovery and which focus on home improvement to prevent flooding, particularly by landlords, might benefit the public health. These results draw awareness and urgency to problems of urban flooding and public health in other areas of the country confronting the compounding challenges of aging infrastructure, disinvestment and climate change.
Is pollen associated with suicide? That’s the question we sought to answer. Pollen related allergic rhinitis is associated with depressive symptoms, discomfort, pain, sleep disruptions, isolation and reduced quality of life in people who have them. Our team, led by UM researcher Dr. Rachel Bergmans, set out to test associations of suicide mortality in Ohio with pollen exposures using data from Ohio’s vital records and a novel prognostic, model based raster of daily pollen counts from Dr. Allison Steiner’s team at UM’s College of Engineering.
We explored associations of suicide with exposure to four types of pollens and the paper can be found here (Open access for 50 days). Suicide is serious. Though the causes of suicide are complex, pollen allergies are associated with depressive symptoms, isolation, pain, discomfort and for some, complete debilitation. #suicide#pollen#epidemiology
Background Seasonal trends in suicide mortality are observed worldwide, potentially aligning with the seasonal release of aeroallergens. However, only a handful of studies have examined whether aeroallergens increase the risk of suicide, with inconclusive results thus far. The goal of this study was to use a time-stratified case-crossover design to test associations of speciated aeroallergens (evergreen, deciduous, grass, and ragweed) with suicide deaths in Ohio, USA (2007–2015).
Methods Residential addresses for 12,646 persons who died by suicide were linked with environmental data at the 4–25 km grid scale including atmospheric aeroallergen concentrations, maximum temperature, sunlight, particulate matter <2.5 μm, and ozone. A case-crossover design was used to examine same-day and 7-day cumulative lag effects on suicide. Analyses were stratified by age group, gender, and educational level.
Results In general, associations were null between aeroallergens and suicide. Stratified analyses revealed a relationship between grass pollen and same-day suicide for women (OR = 3.84; 95% CI = 1.44, 10.22) and those with a high school degree or less (OR = 2.03; 95% CI = 1.18, 3.49).
Conclusions While aeroallergens were generally not significantly related to suicide in this sample, these findings provide suggestive evidence for an acute relationship of grass pollen with suicide for women and those with lower education levels. Further research is warranted to determine whether susceptibility to speciated aeroallergens may be driven by underlying biological mechanisms or variation in exposure levels.
I found this great post on drug shortages that appeared in BMJ today. Among all of the other great gems in it, was this incredibly interesting article on the creation of a mechanical bloodletting device. Jean-Baptiste Sarlandière, a French anatomist and inventor, created the “mechanical leech”, a device intended to extract a controlled amount of blood from the body. Sarlandiere intended the device to replace leeches, which were subject to increasing demand, were becoming expensive, were difficult to cultivate, and were subject to shortages in the Netherlands, who was a large producer of leeches at the time.
A paper was written on the device back in 2009, and within there is a dataset of leech imports and exports to France, which includes data on the monetary value of leeches and public consumption. Of course, I couldn’t resist pulling this data out and doing something with it (despite having better things to do.)
Here is the data, pulled from yet another paper (Alexandre E Baudrimont, Adolphe J Blanqui, et al., Dictionnaire de l’industrie manufacturie`re, commerciale et agricole, Paris, J-B Baillière, 1833–1841, pp. 25–30.):
|Year||Number of leeches imported||Value in Francs||National consumption||Exports||Import export ratio||Value per leech|
Of course, I am fascinated with this. The number of leeches exported from France rose during this period as did the market price of each leech. Though the entire industry would eventually collapse because other medical advances of the nineteenth century would supercede it, it is clear that increased demand and expense led to innovation to create devices to replace it. I don’t know whether the “mechanical leech” led to the development of other medical devices, but would like to think that even batshit ideas like how swamp worms draw out blood to cure any and all medical conditions would lead to the creation of methods which do improve health.
I didn’t hear about this until the very last minute, but was lucky enough to get the invitation letter in time to at least make it to the last day.
The Kenya Medical Research Institute (KEMRI) has, for the past five years, held a research dissemination event intended to highlight KEMRI sponsored and Kenya based research.
Research led by Africans is sadly scarce. R&D funding in SSA is the lowest in the world. In a context where so few people are able to receive an education of sufficient quality to allow post graduate studies, African researchers are few and the resources available to them are low.
Kenya has committed 2% of GDP to R%D. Contrast this with South Korea, which at one point committed 23% of GDP to R&D efforts. While KEMRI is truly a leader in the context of African research, the low level of commitment on the part of the national government makes it tiny in the context of worldwide research.
The presentations I have seen so far have been excellent, but of course, much of this research survives on the good graces of international funding and training. Most of the research presented was performed within the CDC.
So this begs the question, when will and can African countries take ownership of their research? Is this even possible given the dysfunctional nature of politics here?
The story of Africa and African identity (in a global context) is written by the rest of the world. As a foreign researcher, I quite aware that I am part of this phenomenon.
Presenters have pointed to two main issues (which I agree with). First, African countries cannot proceed to develop their research sectors (or any other sector really) unless Africans take charge of in country and continent wide research priorities. It is important to note that foreign research often takes on issues which were of importance in the colonial period (childhood infectious diseases) despite a growing burden of chronic diseases and diseases of aging which will break the budgets and economies of African countries.
While I do not suggest that attention be diverted from the incredible burden of infectious disease in African countries, it is telling that research priorities are still driven by the international community. Central Province in Kenya is quite well developed. Even my taxi drivers ask me why we don’t do research in Central, given the incredible problems of heart disease, cancer and alcoholism up there. Unless Kenyans spearhead the main issues impacting their country, these problems will go unadressed.
Second, as noted before, governments have to make firm commitments to support domestic research. As of now, African countries wait for international funding to support their projects, which shifts the conversation away from domestic priorities to international priorities. This is a tall order here, of course.
Of interest, though, besides the macro level problems of funding and support, presenters passionately call for people with Masters and PhD to use the degrees. “Why don’t you do research? What is wrong with you?”
I can’t speak to this issue effectively. But my sense is that many capable people don’t sense the urgency of doing research and lack the personal initiative to make it happen. I’ve seen it happen that researchers wait to have foreigners write their research for them, and simply wait to have their name rubber stamped on the paper, taking credit for work that they did not do. This is an unacceptable situation that we, unfortunately, enable. Certainly there are issues of experience and capability, but we shouldn’t handle capable African researchers with kid gloves, particularly this well educated young generation.
Sadly, the history of aid and foreign involvement here has set this precedent. This is an era that needs to come to an end. In the private sector, it has. In the public sector, these problems persist. Older researchers, many of whom came of age during the beginnings of the post-independence era, here are screaming that point at the top of their lungs.
Often people will mention that we are “adapted” to do this or another thing, either indicating some crime of modernity (of course, ignoring the fact that a larger percentage of babies are surviving and people are living longer and healthier than at any time in human history) or trying to point out some example of the glaring perfection of our creation, with either an implicit or vocal reference to divine creation.
For example, obesity is attributed to fat and protein rich modern diets since we aren’t “adapted” to eat these types of foods (despite having found the food in East Africa so unpalatable that we had to learn to crush or cook it to digest it efficiently). Our bad disposition is blamed on a lack of sleep since we aren’t “adapted” to sleep as little as we do (this might be true). Most recently, a book writer blamed our problems with depression on a divorced relationship to nature, given that we are “adapted” to hunt and kill for food and then revel over the blood stained corpse (of course, the writer doesn’t consider that people in antiquity might have been depressed, too).
There may be some truth to some of this. However, “adaptation” implies something about the individual, when evolution, in fact, is about reproduction. We aren’t “adapted” to anything. Rather, certain traits are selected for based on the survival of at least two generations of living things, at least for complex social animals like ourselves.
Simply surviving as an individual does not insure the survival of a species. Living things must first survive long enough to reproduce and then, at least in humans, insure that the children make it to reproductive age. Human babies are horribly weak in contrast to sharks, which are ready to go even before they leave the mother. Further, in the case of humans, a full three generations must live at once to insure long term survival.
Thus, we maintain a tenuous relationship with out environment, where traits do not necessarily favor a single individual, but rather an entire family unit, and these traits may or may not imply perfect harmony with an environment, but rather do the job at least satisfactorily.
Nature cares little for quality as numerous examples throughout our physiology show. To claim that we are somehow “perfectly suited” to a specific environment is just simply wrong. Merely, we have come to a brokered peace (after generations of brutal trial and error, what we eat today is thanks to the deaths of millions, mostly children, who had to die to allow us to do so) with wherever we live in order to allow a few of our kids and grandkids to survive.
This, of course, has deep implications for public health. Some public health problems are known to be passed down from parents to children, but in a multi-generational evolutionary framework, it is possible that certain public health problems can be passed through 3 or more generations at a time, complicating interventions. Certainly, the multi-generational health problems of the descendants of African slaves can be an example of this. How can we intervene to protect the public health over a full century?
OK, back to work.