Monday, July 8, 2013 C9
HEALTH HITS AND MYTHS: STRESS AND HAIR LOSS ................................................ Sasha Gonzales life@scmp.com
JOLTED STATES
Q: Can stress cause hair loss?
Sending small pulses of electricity to the brain can relieve the symptoms of Parkinson’s disease and other neurological conditions, writes David Tan
Deep brain stimulation uses a surgically implanted medical device, similar to a pacemaker, to deliver mild electrical pulses to precisely targeted areas of the brain.
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ires inserted into the brain delivering jolts of electricity able to alter movement and behaviour may sound like the stuff of a sci-fi movie. But for people suffering from certain neurological conditions, this scenario is real and offers a much-needed source of relief. Over the past two decades, doctors have turned to deep brain stimulation (DBS) to help people with Parkinson’s disease, and movement disorders like essential tremor and primary dystonia, a debilitating condition that causes painful, twisting muscle spasms. It’s already an established treatment for advanced stages of Parkinson’s that medication alone can no longer treat. Although it’s not a cure, and doesn’t halt disease progression, for certain patients it can vastly improve symptoms such as tremors and muscle rigidity that could make the patient dependent on a caregiver. But the therapy is no longer seen as a last resort. It’s also being applied to earlier stages of Parkinson’s. Scientists are also exploring other applications for the therapy: to treat obesity, Alzheimer’s disease and psychiatric conditions such as depression and obsessivecompulsive disorder. Chronic stimulation of subcortical structures was first used in the early 1950s, but the modern form of DBS, developed in 1987, can be attributed to Alim-Louis Benabid and Pierre Pollak of the University of Grenoble’s department of neurosurgery and neurology in France. The surgery evolved out of the surgeries in which doctors used heat probes to burn and permanently damage small regions of the brain that are
and early motor complications. known to trigger certain The study’s lead investigator, Dr neurological conditions. Günther Deuschl, a professor of In DBS, instead of destroying neurology at Christiantissue, a neurosurgeon implants Albrechts-University in Kiel, slender millimetre-thick Germany, says: “These results electrodes that pump steady signal a shift in the way patients electrical pulses via a batterywith Parkinson’s disease can be powered device – a “brain treated.” pacemaker” – that’s implanted In Singapore, about one or in the chest. two cases of DBS are performed The device is programmed each month at the National externally with a remote, handNeuroscience Institute, held controller to fine-tune according to Professor Ng Waithe electrical stimulation for hoe, head of the institute’s individual patients. neurosurgery department. “At The US Food and Drug present, we normally offer DBS Administration approved the to [Parkinson’s] patients with surgery for “essential tremor” in moderate disease severity; that 1997 and for tremors associated with Parkinson’s disease in 2002. is, when patients begin to experience problems with their DBS was first introduced in motor system or when they Hong Kong in 2007 at the Prince develop adverse effects from of Wales Hospital. The first medication,” Ng says. patient benefited from the “The surgery takes two to treatment for more than 16 years three hours but can vary and had to undergo battery depending on the technique changes only twice at six-year used by the functional intervals, according to Professor neurosurgeon. At the National Poon Wai-sang, chief of Neuroscience Institute, we make neurosurgery at Chinese use of both anatomical targeting University. and microelectrode recording to Benefits vary among patients place the electrode.” according to the severity of their A new, safer way to perform condition. “Our initial selection the surgery, detailed in an article of patients was conservative – last month in the Journal of choosing the most disabled Neurosurgery, could expand patients. [But] it turned out that the moderately disabled patients significantly the number of patients who might be benefited most,” Poon says. candidates for DBS surgery. A recent two-year clinical Using advances in brain trial found it might improve imaging, the new technique – overall quality of life and social tested in 60 patients – allows for functioning in patients in earlier extremely accurate stages of Parkinson’s, too. In electrode the past, doctors have placement. relied solely on drugs in Implanting this period. them is The study, painstaking: published in it starts with February in the New boring a hole England Journal of through the Medicine, showed The year deep brain skull and that DBS was more stimulation was first threading the effective than other introduced in Hong Kong electrodes medical treatment deep into the in patients with brain, aiming for a Parkinson’s disease
2007
DBS could quickly become a treatment for people who have obesity DR CASEY HALPERN
spot that’s a fraction of the size of a pea. “Patients don’t need to be awake during this surgery – which will mean many more patients who can be helped by this surgery will now be willing to consider it,” says Dr Kim Burchiel, chair of neurological surgery at Oregon Health & Science University and lead author of the study. Apart from Parkinson’s, DBS is now also being tested for Alzheimer’s, another form of dementia that also has no cure and is not easily managed. Dr Douglas Scharre, from the Ohio State Wexner Medical Centre in the US, says the disease is progressively disabling, with loss of memory, cognition and worsening behavioural function. His team enrols patients with mild or early-stage Alzheimer’s to determine whether DBS treatment can improve brain function involved in cognition and behaviour. DBS could also help people with conditions such as intractable depression, refractory epilepsy, obsessive compulsive disorders and drug addiction. Addiction can take many forms, including binge eating and alcohol dependence – both of which are being targeted with DBS therapy. In mice and people who overeat compulsively, scientists have
LAB REPORT ......................................................................................... Jeanette Wang jeanette.wang@scmp.com Baby marks the ‘next generation’ A British woman’s newborn last month became the first baby to be born after being screened using a new genome-mapping technique known as “next-generation sequencing”. The method – reported today by Dr Dagan Wells of Oxford University’s NIHR Biomedical Research Centre, who led the study’s international research team – can decode entire genomes (a person’s complete hereditary information). It can reveal data about serious inherited disorders or deadly chromosome abnormalities, which scientists speculate add to the high failure rate of in vitro fertilisation. Only about 30 per cent of embryos selected for transfer actually implant. “[The sequencing] improves our ability to detect these abnormalities and helps us identify the embryos with the best chances of producing a viable pregnancy,” Well says. “Potentially, this should lead to improved in vitro success rates and a lower risk of miscarriage.”
Clues on squeeze in breast milk Researchers have revealed in detail the blueprint for making milk in the human mammary gland, uncovering why many mothers have difficulty making enough milk to breastfeed. Insulin plays a key role in the lactation process, say scientists from the Cincinnati Children’s Hospital Medical Centre and the University of California, Davis. The new study shows a “dramatic switching-on” of the insulin receptor and its downstream signals when the breast turns into a “biofactory that [produces] massive amounts of proteins, fats and carbohydrates for nourishing the newborn”, says Dr Laurie Nommsen-Rivers, the study’s author. “Considering that 20 per cent of women between 20 and 44 are prediabetic [or almost, but not completely diabetic], it’s conceivable that up to 20 per cent of new mothers in the United States are at risk for low milk supply due to insulin dysregulation,” she says. Cooling fears of Sars-like pandemic Researchers have found that the risk for a pandemic triggered by the Sars-like coronavirus is low – at least for now. The findings come amid concerns about a virus spread more deadly than that caused by severe acute respiratory syndrome. Researchers from Institut Pasteur in Paris analysed data – 55 of the 64 laboratory-confirmed cases worldwide – on the novel Middle East respiratory syndrome coronavirus (MERSCoV). “[The virus] has not spread as rapidly or as widely as Sars did,” says lead researcher Arnaud Fontanet, adding that the coronavirus did not mutate into pandemic form despite circulating among humans for more than a year. Still, researchers urge vigilance to prevent the global spread of the virus. No one has tested positive for it in Hong Kong as yet. A 51-year-old man suspected of infection tested negative last week.
pinpointed an abnormality in the regulation of the brain’s reward system. Through tests on obesity-prone mice, researchers at the University of Pennsylvania in the US reported in April that DBS reduces binge eating. “Once replicated in human clinical trials, DBS could rapidly become a treatment for people with obesity due to the extensive groundwork already established in other disease areas,” says study lead author Dr Casey Halpern. For alcoholism, lab tests on rats have shown that DBS consistently reduced alcohol consumption in the rodents. Tests on human alcoholics show that DBS treatment produced less risky and more controlled behaviour accompanied by reduced drinking. Intriguingly, while the effects of DBS are reportedly reversible, doctors have been surprised to find patients who continued to enjoy symptom relief even after their devices were switched off. A recent study reported that two patients being treated for dystonia had their DBS devices accidentally switched off for months, but they only noticed it when mild symptoms returned. Dr Michele Tagliati, director of the movement disorders programme at Cedars-Sinai Department of Neurology in the US, says: “Current thought is that symptoms will worsen within hours or days of device shut-off, but these two young men continued to have clinical benefit despite interruption of DBS therapy for several months. “To our knowledge, these two cases represent the longest duration of retained benefit in primary generalised dystonia.” Moreover, when these patients’ symptoms did return, the severity was far milder than it was before DBS, Tagliati says. life@scmp.com
The straight answer: yes The facts: losing up to 100 hairs a day is normal. But when we are under constant stress, we might shed far more than we would through daily washing, brushing and combing. Stress also makes it difficult for hair to grow back. When the body is stressed, its vitamin B12 supply gets depleted at a rapid pace, and this affects the hair growth cycle. Vitamin B12 helps deliver blood, oxygen and nutrients to the body’s tissues, and as hair is a nonessential tissue, it is the first to experience the effects of a deficiency in this vitamin. This means we simply lose hair faster, says Leonica Kei, a hair and scalp specialist at the Philip Kingsley Trichological Centre in Singapore. Vitamin B12 is mostly found in animal products, particularly clams, mussels, oysters and liver, so if you are a vegetarian or crash-dieter, you might be lacking this nutrient. But a stressful lifestyle makes you two times as likely to suffer from excessive hair loss. Stressful events and major illnesses can also upset the body’s hormonal balance, leading to hair loss. It is common for women, for example, to lose a lot of hair weeks or months after childbirth due to a drop in oestrogen levels. Hair follicles are very sensitive to hormonal changes, says Kei, and a hormonal imbalance tends to make them shrink, thereby producing thinner hair. In some cases of extreme emotional stress, the body’s
It is not easy to attribute hair loss to stress as there is no way to measure stress LEONICA KEI, TRICHOLOGIST
immune system may even mistake the hair follicle for a foreign entity and attack it, causing patchy hair loss, or alopecia areata (an autoimmune disorder, of which stress is thought to be a contributing factor). A stressful week at work is not likely to cause hair loss, but consecutive weeks or months might. When the body is subjected to intense physical and emotional stressors over a prolonged period, stress hormones can trigger most of the hairs on the scalp to enter the telogen phase (the normal resting phase of the hair follicle), causing all of them to fall out – a condition known as telogen effluvium, says Dr John Yu, a specialist in dermatology and venereology at Matilda International Hospital. Stress may also reduce blood flow to the scalp, depriving the follicles of nutrients and interfering with the person’s hair growth cycle. In some people, stress can trigger a psychological disorder known as trichotillomania, or compulsive hair-pulling. For those with this condition, pulling their hair out helps them deal with negative emotions such as tension and anxiety, offering them a sense of pleasure, gratification and relief. Kei says it is not easy to attribute hair loss to stress because there is no real way to measure stress. Also, more often than not, hair loss is not due to one factor but a combination of different factors. If you have been losing hair excessively it’s important to see a trichologist who will be able to diagnose you. A blood test can help rule out any nutritional deficiencies and major health issues. Unfortunately, there is no proven method to minimise hair loss that has occurred as a result of stress, according to Yu. Instead, experts suggest finding ways to get your stress under control and learning how to manage situations that may bring about emotional or physical stress. A healthy, balanced diet will also provide all the essentials you need for normal, healthy hair growth.
Stress can trigger hormones that hamper hair growth. Photo: Corbis