"heightened trend" is correct and can be used in written English.
You can use it to describe a trend that has increased in intensity or magnitude over time. For example, "The heightened trend in online shopping shows that more people are turning to the internet to buy goods."
Certainly, their responses to September 11 heightened that trend by quite a bit, but it was there.
Mass production also heightened the trend toward an international division of labour.
The Richard & Judy effect has heightened a trend that was already apparent in the book market: towards a greater concentration of promotional efforts behind fewer titles.
Both trends heightened and broadened my engagement with picture-taking.
This trend has heightened policy interest in finding alternatives to disability benefit receipt-including employment-to promote economic well-being of people with disabilities and to alleviate fiscal pressures on the SSA trust fund and federal budget.
At the root of this downward trend is heightened competition from other states offering more enticing tax incentives to filmmakers as well as legislative battles about California's own tax credit program.
MetS pigs demonstrated higher platelet aggregation in response to collagen than lean pigs (area under the curve: 286 ± 74 vs 198 ± 123; P = 0.037) and a trend for heightened response to AA (AUC: 260 ± 151 vs 178 ± 145; P = 0.13).
These observations exist in spite of the fact that there is a trend towards heightened Smad3 phosphorylation and nuclear localization in SSc fibroblasts compared to their healthy counterparts [ 8].
Given that toxicokinetics and metabolism data from experimental animal and limited human studies indicate potential sensitivity to the maternal-fetal unit and infant, and that animal studies suggest a trend towards heightened susceptibility during early stages of development in rodents, it is considered appropriate to apply a precautionary approach when characterizing risk.
Two parallel trends have heightened the importance and prevalence of such inequalities.
